Allow the User to Resize Controls at Runtime

Thank you so much for uploading this code, it helped me a lot.

Good job, this is exactly what I needed and the best thing is that it works in the latest version of Visual Studio!

Thank you very much!!! Big Grin | :-D

Ladies and gentlemen,
I am working on a drag and drop application where the user might drag and drop any number of user controls. They all have to be movable and resizable, so I thought I'd copy to routines (mouse down, mouse up, mouse move, mouse leave, the enumeration, and the five variables defined in the class) into the user control class so that it will always be there no matter how many of these controls the user drags and drops. One of these user controls is simply a circle with the following OnPaint event

VB.NET

Private Sub Button1_Paint(sender As Object, e As System.Windows.Forms.PaintEventArgs) Handles Button1.Paint
        Dim myGraphicsPath As New System.Drawing.Drawing2D.GraphicsPath()
        Dim bX As Integer = Button1.Width
        Dim bY As Integer = Button1.Height
        myGraphicsPath.AddEllipse(New Rectangle(0, 0, bX, bY))
        Button1.Region = New Region(myGraphicsPath)
End Sub

I hope I can explain this clearly, here is what's happening:
When (with the mouse clicked) I move the cursor to the right of the control (the cursor does change and show the fuscia color. As I begin to expand to the circle (to make it an ellipse) and move to the right, the right half of the circle is NOT showing. It is disappearing. Only half of it is showing.

When I investigated the size of the button, Bx did actually change. The size is changing.

Another way to phrase the problem, it seems to only show the control in the region where it originally was, of whatever fits in the original box.

If I try to move it to a completely different location, it also disappears.

I would appreciate any feedback.

Alright folks, I think I solved the problem. Apparently, when it comes to user controls, there is the user control itself and the control inside it. In my case, a button with its own paint sub. When I was resizing the control, the container (the user control itself) was not being resized. similarly, when I move the button, the user control was not being moved. To overcome this, I changed my Paint subroutine as follows:

VB.NET

Private Sub Button1_Paint(sender As Object, e As System.Windows.Forms.PaintEventArgs) Handles Button1.Paint
        Dim myGraphicsPath As New System.Drawing.Drawing2D.GraphicsPath()
        Dim bX As Integer = Button1.Width
        Dim bY As Integer = Button1.Height
        Me.Width = bX  ' These two lines adjust the size of the user control to match the button
        Me.Height = bY '  
        myGraphicsPath.AddEllipse(New Rectangle(0, 0, bX, bY))
        Button1.Region = New Region(myGraphicsPath)
    End Sub

In addition, I added a locationchanged sub as follows:

VB.NET

Private Sub Button1_LocationChanged(sender As Object, e As System.EventArgs) Handles Button1.LocationChanged
        Dim Px As Integer = Me.Location.X
        Dim Py As Integer = Me.Location.Y
        Me.Location = New Point(Px + Button1.Location.X, Py + Button1.Location.Y)
        Button1.Location = New Point(0, 0)
End Sub

The above moves the user control to where the button is.

There might be a more elegant way to do this, but this works.

Hello, this is amazing work. well done.

I was wandering if anybody could help to implement it to work with 2row and/or 2column TableLayoutPane and to be able to resize the each column or row in TableLayoutPanel?

many thanks in advance.

I have "translated" the code to C#. I have picked Josh-Mason11's version, I think it was more complete, (although was not standard Poke tongue | ;-P

).

My congratulations to Jesse Chunn, after 8 years, his code remains being very useful.

C#

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace CodyShop_MKeyBoardEditor
{
    class ResizeableControl
    {

        /* ****** TO USE: ********************************************************** *
         * Ex. "ResizeableControl RC = new ResizeableControl(button1);"
         * ************************************************************************* */


        private Control mControl;
        private bool mMouseDown = false;
        private EdgeEnum mEdge = EdgeEnum.None;
        private int mWidth = 8;
        private bool mOutlineDrawn = false;
        int mouseX;
        int mouseY;

        private enum EdgeEnum
        {
            None,
            Right,
            Left,
            Top,
            Bottom,
            Moving,
            BottomRight,
            BottomLeft,
            TopLeft,
            TopRight
        };




        public ResizeableControl(Control Control)
        {
            mControl = Control;

            mControl.MouseDown += new System.Windows.Forms.MouseEventHandler(mControl_MouseDown);
            mControl.MouseUp += new System.Windows.Forms.MouseEventHandler(mControl_MouseUp);
            mControl.MouseMove += new System.Windows.Forms.MouseEventHandler(mControl_MouseMove);
            mControl.MouseLeave += new System.EventHandler(mControl_MouseLeave);
        }

        private void mControl_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            //this.pPantallaVentas.Refresh();
            mouseX = e.X;
            mouseY = e.Y;
            if (e.Button == System.Windows.Forms.MouseButtons.Left)
            {
                mMouseDown = true;
            }
        }

        private void mControl_MouseUp(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            mMouseDown = false;
        }



        private Control SelControl;
        private void mControl_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            Control c = ((Control)sender);
            Graphics g = c.CreateGraphics();
            switch (mEdge)
            {
                case EdgeEnum.Moving:
                    mOutlineDrawn = true;
                    break;
                case EdgeEnum.BottomRight:
                    DrawOrangeSquares(c, g);
                    g.FillRectangle(Brushes.Fuchsia, c.Width - mWidth, c.Height - mWidth, mWidth, mWidth);
                    mOutlineDrawn = true;
                    break;
                case EdgeEnum.BottomLeft:
                    DrawOrangeSquares(c, g);
                    g.FillRectangle(Brushes.Fuchsia, 0, c.Height - mWidth, mWidth, mWidth);
                    mOutlineDrawn = true;
                    break;
                case EdgeEnum.TopRight:
                    DrawOrangeSquares(c, g);
                    g.FillRectangle(Brushes.Fuchsia, c.Width - mWidth, 0, mWidth, mWidth); //top right
                    mOutlineDrawn = true;
                    break;
                case EdgeEnum.TopLeft:
                    DrawOrangeSquares(c, g);
                    g.FillRectangle(Brushes.Fuchsia, 0, 0, mWidth, mWidth); //top left
                    mOutlineDrawn = true;
                    break;
                case EdgeEnum.Left:
                    DrawOrangeSquares(c, g);
                    g.FillRectangle(Brushes.Fuchsia, 0, c.Height / 2 - 4, mWidth, mWidth); //left
                    mOutlineDrawn = true;
                    break;
                case EdgeEnum.Right:
                    DrawOrangeSquares(c, g);
                    g.FillRectangle(Brushes.Fuchsia, c.Width - mWidth, c.Height / 2 - 4, mWidth, mWidth); //right
                    mOutlineDrawn = true;
                    break;
                case EdgeEnum.Top:
                    DrawOrangeSquares(c, g);
                    g.FillRectangle(Brushes.Fuchsia, c.Width / 2 - 4, 0, mWidth, mWidth); //top
                    mOutlineDrawn = true;
                    break;
                case EdgeEnum.Bottom:
                    DrawOrangeSquares(c, g);
                    g.FillRectangle(Brushes.Fuchsia, c.Width / 2 - 4, c.Height - mWidth, mWidth, mWidth); //bottom
                    mOutlineDrawn = true;
                    break;
                case EdgeEnum.None:
                    if (mOutlineDrawn)
                    {
                        c.Refresh();
                        mOutlineDrawn = false;
                    }
                    break;
            }

            if (mMouseDown & mEdge != EdgeEnum.None)
            {
                //MessageBox.Show(Convert.ToString(c));
                c.SuspendLayout();
                switch (mEdge)
                {
                    case EdgeEnum.TopRight:
                        c.SetBounds(c.Left, c.Top, c.Width - (c.Width - e.X), c.Height);
                        c.SetBounds(c.Left, c.Top + e.Y, c.Width, c.Height - e.Y);
                        break;
                    case EdgeEnum.TopLeft:
                        c.SetBounds(c.Left + e.X, c.Top, c.Width - e.X, c.Height);
                        c.SetBounds(c.Left, c.Top + e.Y, c.Width, c.Height - e.Y);
                        break;
                    case EdgeEnum.BottomRight:
                        c.SetBounds(c.Left, c.Top, c.Width - (c.Width - e.X), c.Height);
                        c.SetBounds(c.Left, c.Top, c.Width, c.Height - (c.Height - e.Y));
                        break;
                    case EdgeEnum.BottomLeft:
                        c.SetBounds(c.Left + e.X, c.Top, c.Width - e.X, c.Height);
                        c.SetBounds(c.Left, c.Top, c.Width, c.Height - (c.Height - e.Y));
                        break;
                    case EdgeEnum.Left:
                        c.SetBounds(c.Left + e.X, c.Top, c.Width - e.X, c.Height);
                        break;
                    case EdgeEnum.Right:
                        c.SetBounds(c.Left, c.Top, c.Width - (c.Width - e.X), c.Height);
                        break;
                    case EdgeEnum.Top:
                        c.SetBounds(c.Left, c.Top + e.Y, c.Width, c.Height - e.Y);
                        break;
                    case EdgeEnum.Bottom:
                        c.SetBounds(c.Left, c.Top, c.Width, c.Height - (c.Height - e.Y));
                        break;
                    case EdgeEnum.Moving:
                        c.SetBounds(c.Left + e.X - mouseX, c.Top + e.Y - mouseY, c.Width, c.Height);
                        break;
                }
                c.ResumeLayout();
            }
            else
            {

                if (e.X > c.Width - (mWidth) & e.Y > c.Height - (mWidth)) //Bottom right corner
                {
                    c.Cursor = Cursors.SizeNWSE;
                    mEdge = EdgeEnum.BottomRight;
                }
                else if (e.X <= mWidth & e.Y > c.Height - (mWidth)) //Bottom Left corner
                {
                    c.Cursor = Cursors.SizeNESW;
                    mEdge = EdgeEnum.BottomLeft;
                }
                else if (e.X > c.Width - (mWidth) & e.Y <= mWidth) //Top Right corner
                {
                    c.Cursor = Cursors.SizeNESW;
                    mEdge = EdgeEnum.TopRight;
                }
                else if (e.X <= mWidth & e.Y <= mWidth) //Top Left corner
                {
                    c.Cursor = Cursors.SizeNWSE;
                    mEdge = EdgeEnum.TopLeft;
                }
                else if (e.X <= mWidth & e.Y >= c.Height / 2 - 4 & e.Y <= c.Height / 2 + 4) //left edge
                {
                    c.Cursor = Cursors.SizeWE;
                    mEdge = EdgeEnum.Left;
                }
                else if (e.X >= c.Width - mWidth & e.Y >= c.Height / 2 - 4 & e.Y <= c.Height / 2 + 4) //right edge
                {
                    c.Cursor = Cursors.SizeWE;
                    mEdge = EdgeEnum.Right;
                }
                else if (e.X >= c.Width / 2 - 4 & e.X <= c.Width / 2 + 4 & e.Y <= mWidth) //top edge
                {
                    c.Cursor = Cursors.SizeNS;
                    mEdge = EdgeEnum.Top;
                }
                else if (e.X >= c.Width / 2 - 4 & e.X <= c.Width / 2 + 4 & e.Y >= c.Height - mWidth) //bottom edge
                {
                    c.Cursor = Cursors.SizeNS;
                    mEdge = EdgeEnum.Bottom;
                }
                else if (e.X <= c.Width & e.Y <= c.Height) //move
                {
                    c.Cursor = Cursors.SizeAll;
                    mEdge = EdgeEnum.Moving;
                    DrawOrangeSquares(c, g);
                }
                else                        //no edge
                {
                    c.Cursor = Cursors.Default;
                    mEdge = EdgeEnum.None;
                }


            }


        }

        private void mControl_MouseLeave(object sender, System.EventArgs e)
        {

            Control c = ((Control)sender);
            mEdge = EdgeEnum.None;
            c.Refresh();
            c.Cursor = Cursors.Default;

        }

        internal void DrawOrangeSquares(Control c, Graphics g)
        {

            g.FillRectangle(Brushes.White, c.Width - mWidth - 1, c.Height - mWidth - 1, mWidth + 1, mWidth + 1);
            g.FillRectangle(Brushes.OrangeRed, c.Width - mWidth, c.Height - mWidth, mWidth, mWidth); //bottom right

            g.FillRectangle(Brushes.White, 0, c.Height - mWidth - 1, mWidth + 1, mWidth + 1);
            g.FillRectangle(Brushes.OrangeRed, 0, c.Height - mWidth, mWidth, mWidth); //bottom left

            g.FillRectangle(Brushes.White, 0, c.Height / 2 - 5, mWidth + 1, mWidth + 2);
            g.FillRectangle(Brushes.OrangeRed, 0, c.Height / 2 - 4, mWidth, mWidth); //left

            g.FillRectangle(Brushes.White, c.Width - mWidth - 1, c.Height / 2 - 5, mWidth + 1, mWidth + 2);
            g.FillRectangle(Brushes.OrangeRed, c.Width - mWidth, c.Height / 2 - 4, mWidth, mWidth); //right

            g.FillRectangle(Brushes.White, c.Width / 2 - 5, 0, mWidth + 2, mWidth + 1);
            g.FillRectangle(Brushes.OrangeRed, c.Width / 2 - 4, 0, mWidth, mWidth); //top

            g.FillRectangle(Brushes.White, c.Width / 2 - 5, c.Height - mWidth - 1, mWidth + 2, mWidth + 1);
            g.FillRectangle(Brushes.OrangeRed, c.Width / 2 - 4, c.Height - mWidth, mWidth, mWidth); //bottom

            g.FillRectangle(Brushes.White, c.Width - mWidth - 1, 0, mWidth + 1, mWidth + 1);
            g.FillRectangle(Brushes.OrangeRed, c.Width - mWidth, 0, mWidth, mWidth); //top right

            g.FillRectangle(Brushes.White, 0, 0, mWidth + 1, mWidth + 1);
            g.FillRectangle(Brushes.OrangeRed, 0, 0, mWidth, mWidth); //top left
        }


    }
}

Regards.

Sweet. Thanks for the translation, and good job using the updated code.

Standard answer: It can be done in two weeks, provided nothing unexpected happens.

HOW DO I CHANGE THE FUCHSIA BORDERS WITH SIZING HANDLES? Smile | :)

Hi folks,

I tried the code here and was very impressed - having just started out on switching to VB.Net using Studio 2013, I found this a great learning experience. Below I have modified the code SLIGHTLY - I modified it because on Studio 2013, the bottom and right resize wasn't working - I believe they have changed things slightly? Either way this code is optimised for STUDIO 2013 - I haven't tested it on any other version. I did try to use the previous reply`s code but it references undeclared objects (Quiz?) and this one does not

The changes

The biggest change is that I changed the names of most of the variables to be descriptive - one of the things I always insisted on as a head programmer was to make everything maximum legible so anyone else can adjust it to suit their needs. I believe with the extra comments and renamed variables I have achieved this

I removed a few unnecessary items in some of the calculations where the math was taking a variable away from the same variable - this was unneccesary because of course the result would always be zero.

I changed the logic ever so slightly so when resizing the edge highlight disappears - its unnecessary because the mouse has already changed to reflect the resize and the user is resizing!

Anyway, I hope this helps someone in some way, the way the original code helped me. Thanks a million to Jesse! You rule

VB

Public Class clsMoveRersize
    Private WithEvents ControlToMove As Control
    Private IsLeftButtonHeld As Boolean = False
    Private ObjectEdge As EdgeEnum = EdgeEnum.None
    Private HighlightWidth As Integer = 4
    Private IsHighlightDrawn As Boolean = False
    Private Enum EdgeEnum
        None
        Right
        Left
        Top
        Bottom
        TopLeft
        BottomRight
    End Enum
    Public Sub New(ByVal SourceControl As Control)
        ControlToMove = SourceControl
    End Sub

    Private Sub ControlToMove_MouseDown(ByVal sender As Object, _
        ByVal MouseStatus As System.Windows.Forms.MouseEventArgs) _
        Handles ControlToMove.MouseDown
        If MouseStatus.Button = Windows.Forms.MouseButtons.Left Then
            IsLeftButtonHeld = True
            sender.Refresh()
            IsHighlightDrawn = False
        End If
    End Sub
    Private Sub ControlToMove_MouseUp(ByVal sender As Object, _
        ByVal MouseStatus As System.Windows.Forms.MouseEventArgs) _
        Handles ControlToMove.MouseUp
        IsLeftButtonHeld = False
    End Sub
    Private Sub ControlToMove_MouseMove(ByVal sender As Object, _
    ByVal MouseStatus As System.Windows.Forms.MouseEventArgs) _
    Handles ControlToMove.MouseMove
        Dim SourceControl As Control = CType(sender, Control)
        Dim GraphicsBuffer As Graphics = SourceControl.CreateGraphics
        If Not IsLeftButtonHeld Then
            Select Case ObjectEdge
                Case EdgeEnum.TopLeft
                    GraphicsBuffer.FillRectangle(Brushes.Fuchsia, 0, 0, HighlightWidth * 4,_
                    HighlightWidth * 4)
                    IsHighlightDrawn = True
                    'Display top left corner pink box to show user the object can be moved
                Case EdgeEnum.Left
                    GraphicsBuffer.FillRectangle(Brushes.Fuchsia, 0, 0, HighlightWidth,_
                    SourceControl.Height)
                    IsHighlightDrawn = True
                    'Display left edge pink strip to show user the object can be Resized LEFT
                Case EdgeEnum.Right
                    GraphicsBuffer.FillRectangle(Brushes.Fuchsia, SourceControl.Width _
                     - HighlightWidth - 5, 0, _
                    SourceControl.Width, SourceControl.Height)
                    IsHighlightDrawn = True
                    'Display Right edge pink strip to show user the object can be Resized RIGHT
                Case EdgeEnum.Top
                    GraphicsBuffer.FillRectangle(Brushes.Fuchsia, 0, 0, SourceControl.Width,_
                    HighlightWidth)
                    IsHighlightDrawn = True
                Case EdgeEnum.Bottom
                    GraphicsBuffer.FillRectangle(Brushes.Fuchsia, 0, SourceControl.Height - _
                    HighlightWidth - 5, SourceControl.Width, HighlightWidth)
                    IsHighlightDrawn = True
                Case EdgeEnum.None
                    'Erase the temporary Highlight by simply refreshing the control
                    If IsHighlightDrawn Then
                        SourceControl.Refresh()
                        IsHighlightDrawn = False
                    End If
            End Select
        End If
        If IsLeftButtonHeld And ObjectEdge <> EdgeEnum.None Then 
            'Control is being manipulated - Do this
            SourceControl.SuspendLayout()
            Select Case ObjectEdge
                Case EdgeEnum.TopLeft
                    'Control is being moved
                    SourceControl.SetBounds(SourceControl.Left + MouseStatus.X, SourceControl.Top _
                    + MouseStatus.Y, SourceControl.Width, SourceControl.Height)
                Case EdgeEnum.Left
                    'Control is being Widened TO THE LEFT
                    SourceControl.SetBounds(SourceControl.Left + MouseStatus.X, SourceControl.Top, _
                    SourceControl.Width - MouseStatus.X, SourceControl.Height)
                Case EdgeEnum.Right
                    'Control is being Widened TO THE RIGHT
                    SourceControl.SetBounds(SourceControl.Left, SourceControl.Top, MouseStatus.X,_
                    SourceControl.Height)
                Case EdgeEnum.Top
                    'Control is being Widened TO THE TOP
                    SourceControl.SetBounds(SourceControl.Left, SourceControl.Top + MouseStatus.Y, _
                    SourceControl.Width, SourceControl.Height - MouseStatus.Y)
                Case EdgeEnum.Bottom
                    'Control is being Widened TO THE BOTTOM
                    SourceControl.SetBounds(SourceControl.Left, SourceControl.Top, _
                    SourceControl.Width, MouseStatus.Y + 8)
            End Select
            SourceControl.ResumeLayout()
        Else
            Select Case True
                Case MouseStatus.X <= (HighlightWidth * 4) And MouseStatus.Y <= (HighlightWidth * 4)
                    'top left corner
                    SourceControl.Cursor = Cursors.SizeAll
                    ObjectEdge = EdgeEnum.TopLeft
                Case MouseStatus.X <= HighlightWidth 'left edge
                    SourceControl.Cursor = Cursors.VSplit
                    ObjectEdge = EdgeEnum.Left
                Case MouseStatus.X > SourceControl.Width - (HighlightWidth + 5) 'right edge
                    SourceControl.Cursor = Cursors.VSplit
                    ObjectEdge = EdgeEnum.Right
                Case MouseStatus.Y <= HighlightWidth 'top edge
                    SourceControl.Cursor = Cursors.HSplit
                    ObjectEdge = EdgeEnum.Top
                Case MouseStatus.Y > SourceControl.Height - (HighlightWidth + 5) 'bottom edge
                    SourceControl.Cursor = Cursors.HSplit
                    ObjectEdge = EdgeEnum.Bottom
                Case Else 'no edge
                    SourceControl.Cursor = Cursors.Default
                    ObjectEdge = EdgeEnum.None
            End Select
        End If
    End Sub
    Private Sub ControlToMove_MouseLeave(ByVal sender As Object, ByVal e As System.EventArgs) _
    Handles ControlToMove.MouseLeave

        Dim SourceControl As Control = CType(sender, Control)
        ObjectEdge = EdgeEnum.None
        SourceControl.Refresh()
    End Sub

End Class

modified 26-Jun-14 8:45am.

I have added the ability to drag the corners, the mouse doesn't jump to the top left corner OnMouseDown and orange blocks, where drag is possible, show up on mousemove as well as changing colourwhen the muse is on one of them.

Public Class ResizeableControl

    Private WithEvents mControl As Control
    Private mMouseDown As Boolean = False
    Private mEdge As EdgeEnum = EdgeEnum.None
    Private mWidth As Integer = 8
    Private mOutlineDrawn As Boolean = False
    Dim mouseX As Integer
    Dim mouseY As Integer

    Private Enum EdgeEnum
        None
        Right
        Left
        Top
        Bottom
        Moving
        BottomRight
        BottomLeft
        TopLeft
        TopRight
    End Enum

    Public Sub New(ByVal Control As Control)
        mControl = Control
    End Sub

    Private Sub mControl_MouseDown(ByVal sender As Object, _
        ByVal e As System.Windows.Forms.MouseEventArgs) _
        Handles mControl.MouseDown
        CreateQuiz.QuizDesignPanel.Refresh()
        mouseX = e.X
        mouseY = e.Y
        If e.Button = Windows.Forms.MouseButtons.Left Then
            mMouseDown = True
            CreateQuiz.ControlCreativePanel.Visible = False
            CreateQuiz.PicCreativePanel.Visible = False
            CreateQuiz.PanelCreativePanel.Visible = False
        End If
    End Sub

    Private Sub mControl_MouseUp(ByVal sender As Object, _
        ByVal e As System.Windows.Forms.MouseEventArgs) _
        Handles mControl.MouseUp
        mMouseDown = False
    End Sub



    Private SelControl As Control
    Private Sub mControl_MouseMove(ByVal sender As Object, _
    ByVal e As System.Windows.Forms.MouseEventArgs) _
    Handles mControl.MouseMove
        Dim c As Control = CType(sender, Control)
        Dim g As Graphics = c.CreateGraphics
        Select Case mEdge
            Case EdgeEnum.Moving
                mOutlineDrawn = True
            Case EdgeEnum.BottomRight
                DrawOrangeSquares(c, g)
                g.FillRectangle(Brushes.Fuchsia, _
           c.Width - mWidth, c.Height - mWidth, mWidth, mWidth)
                mOutlineDrawn = True
            Case EdgeEnum.BottomLeft
                DrawOrangeSquares(c, g)
                g.FillRectangle(Brushes.Fuchsia, _
           0, c.Height - mWidth, mWidth, mWidth)
                mOutlineDrawn = True
            Case EdgeEnum.TopRight
                DrawOrangeSquares(c, g)
                g.FillRectangle(Brushes.Fuchsia, _
                c.Width - mWidth, 0, mWidth, mWidth)    'top right
                mOutlineDrawn = True
            Case EdgeEnum.TopLeft
                DrawOrangeSquares(c, g)
                g.FillRectangle(Brushes.Fuchsia, _
                0, 0, mWidth, mWidth)    'top left
                mOutlineDrawn = True
            Case EdgeEnum.Left
                DrawOrangeSquares(c, g)
                g.FillRectangle(Brushes.Fuchsia, _
                0, c.Height \ 2 - 4, mWidth, mWidth)            'left
                mOutlineDrawn = True
            Case EdgeEnum.TopRight
                DrawOrangeSquares(c, g)
                g.FillRectangle(Brushes.Fuchsia, _
                c.Width - mWidth, 0, mWidth, mWidth)
            Case EdgeEnum.Right
                DrawOrangeSquares(c, g)
                g.FillRectangle(Brushes.Fuchsia, _
                c.Width - mWidth, c.Height \ 2 - 4, mWidth, mWidth)    'right
                mOutlineDrawn = True
            Case EdgeEnum.Top
                DrawOrangeSquares(c, g)
                g.FillRectangle(Brushes.Fuchsia, _
                c.Width \ 2 - 4, 0, mWidth, mWidth)          'top
                mOutlineDrawn = True
            Case EdgeEnum.Bottom
                DrawOrangeSquares(c, g)
                g.FillRectangle(Brushes.Fuchsia, _
                    c.Width \ 2 - 4, c.Height - mWidth, mWidth, mWidth)   'bottom
                mOutlineDrawn = True
            Case EdgeEnum.None
                If mOutlineDrawn Then
                    c.Refresh()
                    mOutlineDrawn = False
                End If
        End Select

        If mMouseDown And mEdge <> EdgeEnum.None Then
            MsgBox(c.ToString)
            c.SuspendLayout()
            Select Case mEdge
                Case EdgeEnum.TopRight
                    c.SetBounds(c.Left, c.Top, _
            c.Width - (c.Width - e.X), c.Height)
                    c.SetBounds(c.Left, c.Top + e.Y, _
            c.Width, c.Height - e.Y)
                Case EdgeEnum.TopLeft
                    c.SetBounds(c.Left + e.X, c.Top, _
             c.Width - e.X, c.Height)
                    c.SetBounds(c.Left, c.Top + e.Y, _
            c.Width, c.Height - e.Y)
                Case EdgeEnum.BottomRight
                    c.SetBounds(c.Left, c.Top, _
                c.Width - (c.Width - e.X), c.Height)
                    c.SetBounds(c.Left, c.Top, _
                c.Width, c.Height - (c.Height - e.Y))
                Case EdgeEnum.BottomLeft
                    c.SetBounds(c.Left + e.X, c.Top, _
            c.Width - e.X, c.Height)
                    c.SetBounds(c.Left, c.Top, _
                c.Width, c.Height - (c.Height - e.Y))
                Case EdgeEnum.Left
                    c.SetBounds(c.Left + e.X, c.Top, _
            c.Width - e.X, c.Height)
                Case EdgeEnum.Right
                    c.SetBounds(c.Left, c.Top, _
            c.Width - (c.Width - e.X), c.Height)
                Case EdgeEnum.Top
                    c.SetBounds(c.Left, c.Top + e.Y, _
            c.Width, c.Height - e.Y)
                Case EdgeEnum.Bottom
                    c.SetBounds(c.Left, c.Top, _
            c.Width, c.Height - (c.Height - e.Y))
                Case EdgeEnum.Moving
                    c.SetBounds(c.Left + e.X - mouseX, c.Top + e.Y - mouseY, _
            c.Width, c.Height)
            End Select
            c.ResumeLayout()
        Else
            Select Case True
                Case e.X > c.Width - (mWidth) And _
                    e.Y > c.Height - (mWidth) 'Bottom right corner
                    c.Cursor = Cursors.SizeNWSE
                    mEdge = EdgeEnum.BottomRight
                Case e.X <= mWidth And _
                   e.Y > c.Height - (mWidth) 'Bottom Left corner
                    c.Cursor = Cursors.SizeNESW
                    mEdge = EdgeEnum.BottomLeft
                Case e.X > c.Width - (mWidth) And _
                    e.Y <= mWidth 'Top Right corner
                    c.Cursor = Cursors.SizeNESW
                    mEdge = EdgeEnum.TopRight
                Case e.X <= mWidth And _
                    e.Y <= mWidth 'Top Left corner
                    c.Cursor = Cursors.SizeNWSE
                    mEdge = EdgeEnum.TopLeft
                Case e.X <= mWidth And _
                    e.Y >= c.Height \ 2 - 4 And e.Y _
                    <= c.Height \ 2 + 4 'left edge
                    c.Cursor = Cursors.SizeWE
                    mEdge = EdgeEnum.Left
                Case e.X >= c.Width - mWidth And _
                    e.Y >= c.Height \ 2 - 4 And e.Y _
                    <= c.Height \ 2 + 4 'right edge
                    c.Cursor = Cursors.SizeWE
                    mEdge = EdgeEnum.Right
                Case e.X >= c.Width \ 2 - 4 And _
                    e.X <= c.Width \ 2 + 4 And _
                    e.Y <= mWidth 'top edge
                    c.Cursor = Cursors.SizeNS
                    mEdge = EdgeEnum.Top
                Case e.X >= c.Width \ 2 - 4 And _
                    e.X <= c.Width \ 2 + 4 And _
                    e.Y >= c.Height - mWidth 'bottom edge
                    c.Cursor = Cursors.SizeNS
                    mEdge = EdgeEnum.Bottom
                Case e.X <= c.Width And e.Y <= c.Height 'move
                    c.Cursor = Cursors.SizeAll
                    mEdge = EdgeEnum.Moving
                    DrawOrangeSquares(c, g)
                Case Else 'no edge
                    c.Cursor = Cursors.Default
                    mEdge = EdgeEnum.None
            End Select
        End If


    End Sub

    Private Sub mControl_MouseLeave(ByVal sender As Object, _
        ByVal e As System.EventArgs) _
        Handles mControl.MouseLeave

        Dim c As Control = CType(sender, Control)
        mEdge = EdgeEnum.None
        c.Refresh()
        c.Cursor = Cursors.Default

    End Sub

    Sub DrawOrangeSquares(c As Control, g As Graphics)

        g.FillRectangle(Brushes.White, _
c.Width - mWidth - 1, c.Height - mWidth - 1, mWidth + 1, mWidth + 1)
        g.FillRectangle(Brushes.OrangeRed, _
c.Width - mWidth, c.Height - mWidth, mWidth, mWidth)   'bottom right

        g.FillRectangle(Brushes.White, _
        0, c.Height - mWidth - 1, mWidth + 1, mWidth + 1)
        g.FillRectangle(Brushes.OrangeRed, _
        0, c.Height - mWidth, mWidth, mWidth)   'bottom left

        g.FillRectangle(Brushes.White, _
        0, c.Height \ 2 - 5, mWidth + 1, mWidth + 2)
        g.FillRectangle(Brushes.OrangeRed, _
        0, c.Height \ 2 - 4, mWidth, mWidth)            'left

        g.FillRectangle(Brushes.White, _
        c.Width - mWidth - 1, c.Height \ 2 - 5, mWidth + 1, mWidth + 2)
        g.FillRectangle(Brushes.OrangeRed, _
        c.Width - mWidth, c.Height \ 2 - 4, mWidth, mWidth)    'right

        g.FillRectangle(Brushes.White, _
        c.Width \ 2 - 5, 0, mWidth + 2, mWidth + 1)
        g.FillRectangle(Brushes.OrangeRed, _
        c.Width \ 2 - 4, 0, mWidth, mWidth)          'top

        g.FillRectangle(Brushes.White, _
        c.Width \ 2 - 5, c.Height - mWidth - 1, mWidth + 2, mWidth + 1)
        g.FillRectangle(Brushes.OrangeRed, _
        c.Width \ 2 - 4, c.Height - mWidth, mWidth, mWidth)   'bottom

        g.FillRectangle(Brushes.White, _
        c.Width - mWidth - 1, 0, mWidth + 1, mWidth + 1)
        g.FillRectangle(Brushes.OrangeRed, _
        c.Width - mWidth, 0, mWidth, mWidth)    'top right

        g.FillRectangle(Brushes.White, _
        0, 0, mWidth + 1, mWidth + 1)
        g.FillRectangle(Brushes.OrangeRed, _
        0, 0, mWidth, mWidth)                'top left
    End Sub

End Class

Not rude at all! I posted this in 2007. It is great to see folks still finding it useful, and even better that you have improved it. That is what this site is all about.
Thanks!

Standard answer: It can be done in two weeks, provided nothing unexpected happens.

Well, it's certainly the best code for it's purpose I could find. It also taught me how to use classes and cases!

A little off topic.
I'm 16 and just starting college. I'm really into code (especially VB.NET at the moment) and would absolutely love a career that involves it. Jut out of interest, if you don't mind saying, how did you get to the position you're at now. Did you take the right courses? Got lucky and recognized by somebody in the business? Or even know the right people? You don't have to say but I would really like to know how to get started (turning a hobby into a profession). Thanks

Well, I know this is a very, very late response, but I'll answer anyway. I started out by learning to program. I went to a local community college while working full time until I got my associates degree in Computer Science. I got a job as a programmer pretty much immediately, which was a big change from the job I had at that time, loading trucks. I actually started out as a programmer making less than I was making loading trucks. I had (and have) a love for programming, so when I was not working, I was at home writing software for all sorts of purposes. I eventually built up a reputation as a "cracker-jack" programmer, and began picking up side-jobs writing software for companies outside of my day job. I got those jobs through people I worked with that had spouses at other companies that needed short-term contract help. Eventually I started my own company and ran that for about a decade before I sold it. The connections I made while running my company (and since) are the primary source of jobs I have had since then. I also got a BS in Business Management along the way (more than a decade after getting my associates degree), all while working full time (way more than 40 hours per week). I didn't get any help from anyone, and paid my way as I went, and I dropped out of high-school (went back as an adult to get diploma), so if I can do it, anybody can. All you need is passion and determination. Period. Everything else will come. And by the way, don't be afraid to branch out to other programming languages. It may seem hard at first, but they are all pretty much the same once you spend a week or two working at it, and each one has strengths and weaknesses depending on what you are trying to do.
Good luck my friend.

Standard answer: It can be done in two weeks, provided nothing unexpected happens.

This is a great solution and it helped me a lot but could somebody please help me out with this.
I would like to add the possibility that if you keep the CTRL key pressed it does a drag with the control instead of resize it.
I am trying this but can't get the event to fire.

Private Sub mControl_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles mControl.KeyDown
' Determine whether the key entered is the Ctrl key. If it is, display Help.

If e.KeyCode = Keys.ControlKey Then
ControlEntered = True
dragging = True
MsgBox("true")
End If

End Sub

Do you still want a solution to this, as I have gotten quite familiar with the class?

Hello everyone, I am fairly new to vbnet (and to programming altogether) and was working on a project that required the user to move and resize picture boxes, so this was extremely helpful.

However, I do have one question if anyone can please answer it. Can anyone tell me exactly which part of the code does the resizing and which one does the moving? This will be very helpful for those of us coming down the learning curve.

How to resize a veritcal scroll bar. It doesnt work with this code ?

Could someone guide me to use this code to make a resizable button when a button is clicked... Confused | :confused:

I lyk 2 thank u in advance for the help.. Roll eyes | :rolleyes:

Very Nice!!

Very usefull,thanks

I love this article. I have modified it little to allow smooth drag.
I am aware that this post is approx. 2 years old...but still I hope it may help someone.

Once again thanks to Jesse

Public Class ResizeableControl

    Private WithEvents mControl As Control
    Private mMouseDown As Boolean = False
    Private mEdge As EdgeEnum = EdgeEnum.None
    Private mWidth As Integer = 4
    Private mOutlineDrawn As Boolean = False

    Private beginX, beginY As Integer

    Public Enum EdgeEnum
        None = 0
        Right = 1
        Left = 2
        Top = 4
        Bottom = 8
        TopLeft = 16
        'added
        All = TopLeft Or Left Or Right Or Top Or Bottom
        ResizeAnchorTopLeft = Right Or Bottom
        OnlyMove = TopLeft
        'end added
    End Enum

    Public Property AllowEdges() As EdgeEnum
        Get
            Return _AllowEdges
        End Get
        Set(ByVal value As EdgeEnum)
            _AllowEdges = value
        End Set
    End Property
    Friend _AllowEdges As EdgeEnum = EdgeEnum.All 'Default Behavior

    Public Property HighlightColor() As Drawing.Color
        Get
            Return _HighlightColor
        End Get
        Set(ByVal value As Drawing.Color)
            _HighlightColor = value
        End Set
    End Property
    Private _HighlightColor As Drawing.Color = Color.Fuchsia

    Public Sub New(ByVal Control As Control)
        mControl = Control
    End Sub
    'added
    Public Sub New(ByVal Control As Control, ByVal AllowedEdges As EdgeEnum)
        mControl = Control
        _AllowEdges = AllowedEdges
    End Sub
    'end added

    Private Sub mControl_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles mControl.MouseDown
        If e.Button = Windows.Forms.MouseButtons.Left Then mMouseDown = True
        beginX = e.X
        beginY = e.Y
    End Sub

    Private Sub mControl_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles mControl.MouseUp
        mMouseDown = False
    End Sub
    'added
    Private mpLast_Location As Point = New Point(0, 0)
    'end added
    Private Sub mControl_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles mControl.MouseMove
        Dim c As Control = CType(sender, Control)
        Dim g As Graphics = c.CreateGraphics

        Dim B As New System.Drawing.SolidBrush(_HighlightColor)
        'added 'Moved from Select Case mEdge : Case EdgeEnum.None 
        If mOutlineDrawn Then
            c.Refresh()
            mOutlineDrawn = False
        End If
        'end added
        Select Case mEdge
            Case EdgeEnum.TopLeft
                g.FillRectangle(B, 0, 0, mWidth * 4, mWidth * 4)
                mOutlineDrawn = True
            Case EdgeEnum.Left
                g.FillRectangle(B, 0, 0, mWidth, c.Height)
                mOutlineDrawn = True
            Case EdgeEnum.Right
                g.FillRectangle(B, c.Width - mWidth, 0, c.Width, c.Height)
                mOutlineDrawn = True
            Case EdgeEnum.Top
                g.FillRectangle(B, 0, 0, c.Width, mWidth)
                mOutlineDrawn = True
            Case EdgeEnum.Bottom
                g.FillRectangle(B, 0, c.Height - mWidth, c.Width, mWidth)
                mOutlineDrawn = True
                'Case EdgeEnum.None 'Moved before Select Case
                '    If mOutlineDrawn Then
                '        c.Refresh()
                '        mOutlineDrawn = False
                '    End If
        End Select

        If mMouseDown And mEdge <> EdgeEnum.None Then
            c.SuspendLayout()
            Select Case mEdge
                Case EdgeEnum.TopLeft
                    c.Location = New Point(c.Location.X + e.X - beginX, c.Location.Y + e.Y - beginY)
                    c.Parent.Refresh()
                    ''added
                    'Dim iX_Delta As Integer = e.X
                    'Dim iY_Delta As Integer = e.Y
                    'If Not (mpLast_Location = New Point(0, 0)) Then
                    '    iX_Delta -= mpLast_Location.X
                    '    iY_Delta -= mpLast_Location.Y
                    'End If
                    'c.SetBounds(c.Left + iX_Delta, c.Top + iY_Delta, c.Width, c.Height)
                    ''end added 
                    ''c.SetBounds(c.Left + e.X, c.Top + e.Y, c.Width, c.Height) 'Original
                    'RaiseEvent ResizeOccurred(c)
                Case EdgeEnum.Left
                    c.SetBounds(c.Left + e.X, c.Top, c.Width - e.X, c.Height)
                    RaiseEvent ResizeOccurred(c)
                Case EdgeEnum.Right
                    c.SetBounds(c.Left, c.Top, c.Width - (c.Width - e.X), c.Height)
                    RaiseEvent ResizeOccurred(c)
                    'added
                    mpLast_Location = e.Location
                    'end added
                Case EdgeEnum.Top
                    c.SetBounds(c.Left, c.Top + e.Y, c.Width, c.Height - e.Y)
                    RaiseEvent ResizeOccurred(c)
                Case EdgeEnum.Bottom
                    c.SetBounds(c.Left, c.Top, c.Width, c.Height - (c.Height - e.Y))
                    RaiseEvent ResizeOccurred(c)
            End Select
            c.ResumeLayout()
        Else
            Select Case True
                Case e.X <= (mWidth * 4) And e.Y <= (mWidth * 4) 'top left corner
                    c.Cursor = Cursors.SizeAll
                    mEdge = EdgeEnum.TopLeft
                Case e.X <= mWidth 'left edge
                    c.Cursor = Cursors.VSplit
                    mEdge = EdgeEnum.Left
                Case e.X > c.Width - (mWidth + 1) 'right edge
                    c.Cursor = Cursors.VSplit
                    mEdge = EdgeEnum.Right
                Case e.Y <= mWidth 'top edge
                    c.Cursor = Cursors.HSplit
                    mEdge = EdgeEnum.Top
                Case e.Y > c.Height - (mWidth + 1) 'bottom edge
                    c.Cursor = Cursors.HSplit
                    mEdge = EdgeEnum.Bottom
                Case Else 'no edge
                    c.Cursor = Cursors.Default
                    mEdge = EdgeEnum.None
            End Select
            mEdge = mEdge And _AllowEdges
            If mEdge = EdgeEnum.None Then c.Cursor = Cursors.Default
        End If
    End Sub

    Private Sub mControl_MouseLeave(ByVal sender As Object, ByVal e As System.EventArgs) Handles mControl.MouseLeave
        Dim c As Control = CType(sender, Control)
        c.Cursor = Cursors.Default
        mEdge = EdgeEnum.None
        c.Refresh()
    End Sub

    Public Event ResizeOccurred(ByRef c As System.Windows.Forms.Control)

End Class

*Fixed the line drawing problem
*Fixed the TopLeft (movement error)
*Added a new Constructor that allow to set the AllowedEdges
*Added Developer-Friendly Smile | :)

Allow-Edges Enums: All, ResizeAnchorTopLeft, OnlyMove

Public Class ResizeableControl

    Private WithEvents mControl As Control
    Private mMouseDown As Boolean = False
    Private mEdge As EdgeEnum = EdgeEnum.None
    Private mWidth As Integer = 4
    Private mOutlineDrawn As Boolean = False

    Public Enum EdgeEnum
        None = 0
        Right = 1
        Left = 2
        Top = 4
        Bottom = 8
        TopLeft = 16
        'added
        All = TopLeft Or Left Or Right Or Top Or Bottom
        ResizeAnchorTopLeft = Right Or Bottom
        OnlyMove = TopLeft
        'end added
    End Enum

    Public Property AllowEdges() As EdgeEnum
        Get
            Return _AllowEdges
        End Get
        Set(ByVal value As EdgeEnum)
            _AllowEdges = value
        End Set
    End Property
    Friend _AllowEdges As EdgeEnum = EdgeEnum.All 'Default Behavior

    Public Property HighlightColor() As Drawing.Color
        Get
            Return _HighlightColor
        End Get
        Set(ByVal value As Drawing.Color)
            _HighlightColor = value
        End Set
    End Property
    Private _HighlightColor As Drawing.Color = Color.Fuchsia

    Public Sub New(ByVal Control As Control)
        mControl = Control
    End Sub
    'added
    Public Sub New(ByVal Control As Control, ByVal AllowedEdges As EdgeEnum)
        mControl = Control
        _AllowEdges = AllowedEdges
    End Sub
    'end added

    Private Sub mControl_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles mControl.MouseDown
        If e.Button = Windows.Forms.MouseButtons.Left Then mMouseDown = True
    End Sub

    Private Sub mControl_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles mControl.MouseUp
        mMouseDown = False
    End Sub
    'added
    Private mpLast_Location As Point = New Point(0, 0)
    'end added
    Private Sub mControl_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles mControl.MouseMove
        Dim c As Control = CType(sender, Control)
        Dim g As Graphics = c.CreateGraphics

        Dim B As New System.Drawing.SolidBrush(_HighlightColor)
        'added 'Moved from Select Case mEdge : Case EdgeEnum.None
        If mOutlineDrawn Then
            c.Refresh()
            mOutlineDrawn = False
        End If
        'end added
        Select Case mEdge
            Case EdgeEnum.TopLeft
                g.FillRectangle(B, 0, 0, mWidth * 4, mWidth * 4)
                mOutlineDrawn = True
            Case EdgeEnum.Left
                g.FillRectangle(B, 0, 0, mWidth, c.Height)
                mOutlineDrawn = True
            Case EdgeEnum.Right
                g.FillRectangle(B, c.Width - mWidth, 0, c.Width, c.Height)
                mOutlineDrawn = True
            Case EdgeEnum.Top
                g.FillRectangle(B, 0, 0, c.Width, mWidth)
                mOutlineDrawn = True
            Case EdgeEnum.Bottom
                g.FillRectangle(B, 0, c.Height - mWidth, c.Width, mWidth)
                mOutlineDrawn = True
                'Case EdgeEnum.None 'Moved before Select Case
                '    If mOutlineDrawn Then
                '        c.Refresh()
                '        mOutlineDrawn = False
                '    End If
        End Select

        If mMouseDown And mEdge <> EdgeEnum.None Then
            c.SuspendLayout()
            Select Case mEdge
                Case EdgeEnum.TopLeft
                    'added
                    Dim iX_Delta As Integer = e.X
                    Dim iY_Delta As Integer = e.Y
                    If Not (mpLast_Location = New Point(0, 0)) Then
                        iX_Delta -= mpLast_Location.X
                        iY_Delta -= mpLast_Location.Y
                    End If
                    c.SetBounds(c.Left + iX_Delta, c.Top + iY_Delta, c.Width, c.Height)
                    'end added
                    'c.SetBounds(c.Left + e.X, c.Top + e.Y, c.Width, c.Height) 'Original
                    RaiseEvent ResizeOccurred(c)
                Case EdgeEnum.Left
                    c.SetBounds(c.Left + e.X, c.Top, c.Width - e.X, c.Height)
                    RaiseEvent ResizeOccurred(c)
                Case EdgeEnum.Right
                    c.SetBounds(c.Left, c.Top, c.Width - (c.Width - e.X), c.Height)
                    RaiseEvent ResizeOccurred(c)
                    'added
                    mpLast_Location = e.Location
                    'end added
                Case EdgeEnum.Top
                    c.SetBounds(c.Left, c.Top + e.Y, c.Width, c.Height - e.Y)
                    RaiseEvent ResizeOccurred(c)
                Case EdgeEnum.Bottom
                    c.SetBounds(c.Left, c.Top, c.Width, c.Height - (c.Height - e.Y))
                    RaiseEvent ResizeOccurred(c)
            End Select
            c.ResumeLayout()
        Else
            Select Case True
                Case e.X <= (mWidth * 4) And e.Y <= (mWidth * 4) 'top left corner
                    c.Cursor = Cursors.SizeAll
                    mEdge = EdgeEnum.TopLeft
                Case e.X <= mWidth 'left edge
                    c.Cursor = Cursors.VSplit
                    mEdge = EdgeEnum.Left
                Case e.X > c.Width - (mWidth + 1) 'right edge
                    c.Cursor = Cursors.VSplit
                    mEdge = EdgeEnum.Right
                Case e.Y <= mWidth 'top edge
                    c.Cursor = Cursors.HSplit
                    mEdge = EdgeEnum.Top
                Case e.Y > c.Height - (mWidth + 1) 'bottom edge
                    c.Cursor = Cursors.HSplit
                    mEdge = EdgeEnum.Bottom
                Case Else 'no edge
                    c.Cursor = Cursors.Default
                    mEdge = EdgeEnum.None
            End Select
            mEdge = mEdge And _AllowEdges
            If mEdge = EdgeEnum.None Then c.Cursor = Cursors.Default
        End If
    End Sub

    Private Sub mControl_MouseLeave(ByVal sender As Object, ByVal e As System.EventArgs) Handles mControl.MouseLeave
        Dim c As Control = CType(sender, Control)
        c.Cursor = Cursors.Default
        mEdge = EdgeEnum.None
        c.Refresh()
    End Sub

    Public Event ResizeOccurred(ByRef c As System.Windows.Forms.Control)

End Class

Been looking for something like this for a while. I code in C++/CLR so I had to do some translating from VB to that language. But I got it working. Thanks

I've come across what I think is a slight problem/snag... If you try to set a resizable control to a control with child controls, getting the mouse on the border is tricky. For example, a Panel control that contains an embedded TextBox. The TextBox's bottom is at the bottom of the Panel (or it's docked to the bottom). When the mouse is over the bottom of the Panel, it'll need to be on the 1-pixel wide bottom border of the Panel for the highlighting/sizing to work. Otherwise the mouse is over the TextBox, the resizing events don't fire, and the resizing cursor doesn't appear.

Does this make sense? Not sure what, if any, workaround there is for this.

Steve

This class is way cool. It worked perfectly for what I needed -- a series of Infragistics UltraExpandableGroupBox controls docked TOP one on top of another (basically forming a vertical 'table' of group boxes. I wanted each of the group boxes to be resizable.

I did make a few tweaks (new code below). I added AllowEdges and HighlightColor properties. I also added values to the enumeration. This, along with the AllowEdges property enable you to specify which edges can be resized. I needed the bottom only, so this worked well. The HighlightColor property lets you set what color the edge highlight is -- fuschia just didn't do it for me! Smile | :)

Finally, I added a ResizeOccurred event that is thrown during the resizing. I handle it to make sure the control isn't resized past a minimum threshold.

I realize that my implementation of these "extras" is pretty quick and simplistic. Just wanted to share these as I thought you might want to add them (or something like them) to your original class.

Steve

Public Class Form1
    Dim rc As ResizeableControl

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        rc = New ResizeableControl(pbDemo)
        rc.HighlightColor = Color.Orange
        rc.AllowEdges = ResizeableControl.EdgeEnum.Bottom
        AddHandler rc.ResizeOccurred, AddressOf HandleResize
    End Sub


    Private Sub HandleResize(ByRef sender As Windows.Forms.Control)
        If sender.Height < 50 Then sender.Height = 50
    End Sub


    Public Class ResizeableControl

        Private WithEvents mControl As Control
        Private mMouseDown As Boolean = False
        Private mEdge As EdgeEnum = EdgeEnum.None
        Private mWidth As Integer = 4
        Private mOutlineDrawn As Boolean = False


        Public Property AllowEdges() As EdgeEnum
            Get
                Return _AllowEdges
            End Get
            Set(ByVal value As EdgeEnum)
                _AllowEdges = value
            End Set
        End Property
        Friend _AllowEdges As EdgeEnum = EdgeEnum.Bottom Or EdgeEnum.Left Or EdgeEnum.Right Or EdgeEnum.Top Or EdgeEnum.TopLeft


        Public Property HighlightColor() As Drawing.Color
            Get
                Return _HighlightColor
            End Get
            Set(ByVal value As Drawing.Color)
                _HighlightColor = value
            End Set
        End Property
        Private _HighlightColor As Drawing.Color = Color.Fuchsia


        Public Enum EdgeEnum
            None = 0
            Right = 1
            Left = 2
            Top = 4
            Bottom = 8
            TopLeft = 16
        End Enum

        Public Sub New(ByVal Control As Control)
            mControl = Control
        End Sub

        Private Sub mControl_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles mControl.MouseDown
            If e.Button = Windows.Forms.MouseButtons.Left Then
                mMouseDown = True
            End If
        End Sub

        Private Sub mControl_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles mControl.MouseUp
            mMouseDown = False
        End Sub

        Private Sub mControl_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles mControl.MouseMove
            Dim c As Control = CType(sender, Control)
            Dim g As Graphics = c.CreateGraphics

            Dim B As New System.Drawing.SolidBrush(_HighlightColor)
            Select Case mEdge
                Case EdgeEnum.TopLeft
                    g.FillRectangle(B, 0, 0, mWidth * 4, mWidth * 4)
                    mOutlineDrawn = True
                Case EdgeEnum.Left
                    g.FillRectangle(B, 0, 0, mWidth, c.Height)
                    mOutlineDrawn = True
                Case EdgeEnum.Right
                    g.FillRectangle(B, c.Width - mWidth, 0, c.Width, c.Height)
                    mOutlineDrawn = True
                Case EdgeEnum.Top
                    g.FillRectangle(B, 0, 0, c.Width, mWidth)
                    mOutlineDrawn = True
                Case EdgeEnum.Bottom
                    g.FillRectangle(B, 0, c.Height - mWidth, c.Width, mWidth)
                    mOutlineDrawn = True
                Case EdgeEnum.None
                    If mOutlineDrawn Then
                        c.Refresh()
                        mOutlineDrawn = False
                    End If
            End Select

            If mMouseDown And mEdge <> EdgeEnum.None Then
                c.SuspendLayout()
                Select Case mEdge
                    Case EdgeEnum.TopLeft
                        c.SetBounds(c.Left + e.X, c.Top + e.Y, c.Width, c.Height)
                        RaiseEvent ResizeOccurred(c)
                    Case EdgeEnum.Left
                        c.SetBounds(c.Left + e.X, c.Top, c.Width - e.X, c.Height)
                        RaiseEvent ResizeOccurred(c)
                    Case EdgeEnum.Right
                        c.SetBounds(c.Left, c.Top, c.Width - (c.Width - e.X), c.Height)
                        RaiseEvent ResizeOccurred(c)
                    Case EdgeEnum.Top
                        c.SetBounds(c.Left, c.Top + e.Y, c.Width, c.Height - e.Y)
                        RaiseEvent ResizeOccurred(c)
                    Case EdgeEnum.Bottom
                        c.SetBounds(c.Left, c.Top, c.Width, c.Height - (c.Height - e.Y))
                        RaiseEvent ResizeOccurred(c)
                End Select
                c.ResumeLayout()
            Else
                Select Case True
                    Case e.X <= (mWidth * 4) And e.Y <= (mWidth * 4) 'top left corner
                        c.Cursor = Cursors.SizeAll
                        mEdge = EdgeEnum.TopLeft
                    Case e.X <= mWidth 'left edge
                        c.Cursor = Cursors.VSplit
                        mEdge = EdgeEnum.Left
                    Case e.X > c.Width - (mWidth + 1) 'right edge
                        c.Cursor = Cursors.VSplit
                        mEdge = EdgeEnum.Right
                    Case e.Y <= mWidth 'top edge
                        c.Cursor = Cursors.HSplit
                        mEdge = EdgeEnum.Top
                    Case e.Y > c.Height - (mWidth + 1) 'bottom edge
                        c.Cursor = Cursors.HSplit
                        mEdge = EdgeEnum.Bottom
                    Case Else 'no edge
                        c.Cursor = Cursors.Default
                        mEdge = EdgeEnum.None
                End Select
                mEdge = mEdge And _AllowEdges
                If mEdge = EdgeEnum.None Then c.Cursor = Cursors.Default
            End If
        End Sub

        Private Sub mControl_MouseLeave(ByVal sender As Object, ByVal e As System.EventArgs) Handles mControl.MouseLeave
            Dim c As Control = CType(sender, Control)
            mEdge = EdgeEnum.None
            c.Refresh()
        End Sub

        Public Event ResizeOccurred(ByRef c As System.Windows.Forms.Control)
    End Class

End Class

Allow the User to Resize Controls at Runtime

Introduction

Background

Using the Code

Points of Interest

History

License

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