Visual Basic

public void SetText(string text) {
    if (myControl.InvokeRequired) {
        // this runs on the foreign thread and causes the
        // invocation of this same method on the GUI thread
        myControl.Invoke(new Action< string >(SetText),
            new object[] {text});
    } else {
        // this runs on the GUI thread only
        myControl.Text=text;
    }
}

architecton wrote:

Is there an event whether the mouse is over the form or not?

I are troll

architecton wrote:

You are right but then i have to write this for each visible control on my form and this is not good because i only need one event and not x.

I are troll

Public sub Test () handles button1.mouseclick , button2.mouseclick
end sub

architecton wrote:

if yes, this is my problem and i try to avoid this

Private Sub ctrl_MouseMove(sender As Object, e As System.Windows.Forms.MouseEventArgs) 
  ' Do your thing here
End Sub

AddHandler Panel1.MouseMove, AddressOf ctrl_MouseMove
AddHandler Panel2.MouseMove, AddressOf ctrl_MouseMove
AddHandler Label5.MouseMove, AddressOf ctrl_MouseMove
[...].

I are troll

Private Sub ctrl_MouseMove(sender As Object, e As System.Windows.Forms.MouseEventArgs) 
    If sender Is Form1 Then
        ' Do your thing here
    Else If sender is control Then
        ' some other actions
    EndIf
End Sub

I are troll

Public Class Form1

    Dim ne As New Point(Me.Top, Me.Left)
    Dim sw As New Point(Me.Top + Me.Height, Me.Left + Me.Width)

   Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        Timer1.Start()
    End Sub

    Private Sub Form1_Move(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Move
        ne = New Point(Me.Top, Me.Left)
        sw = New Point(Me.Top + Me.Height, Me.Left + Me.Width)
    End Sub


    Private Sub Form1_Resize(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Resize
        ne = New Point(Me.Top, Me.Left)
        sw = New Point(Me.Top + Me.Height, Me.Left + Me.Width)
    End Sub

    Private Sub Timer1_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        With Control.MousePosition
            If .X > ne.X And .Y > ne.Y And .X < sw.X And .Y < sw.Y Then
                TextBox1.BackColor = Color.Azure
            Else
                TextBox1.BackColor = Color.White
            End If
        End With
    End Sub

End Class

Dim mySalary As Double = 2000

txtSalary.Text = mySalary.ToString("$0.00")

...

Public Sub txtSalary_Validate(...)...
  If IsNumeric(txtSalary.Text) = True Then
    txtSalary.Text = CDbl(txtSalary.Text).ToString("$0.00")
  End If
End Sub

Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox1.TextChanged
        TextBox1.Text = CDbl(TextBox1.Text).ToString("F")
    End Sub