C# Discussion Boards - CodeProject

6-Mar-06 17:27

I just started playing around with the Mdi Containers. I have one parent and four children that i open inside this parent form. what i want to do is check if a child form is already open inside of this parent, and if so it must be closed first, as to try and avoid the user from opening multiple child forms of the same child, if that makes any sense.

I've tried the Parent.hasChildren()
but that returns true no matter whether a child window is open or not.

Any help will be appreciated

Thanx in advance

DigitalKing6-Mar-06 17:50

6-Mar-06 17:50

Do something like this:

private void newWindowType1ToolStripMenuItem_Click(object sender, EventArgs e)
{
   if (!ContainsChildForm(typeof(child1)))
   {
       child1 c = new child1();
       c.MdiParent = this;
       c.Show();
   }
}

private void newWindowType2ToolStripMenuItem_Click(object sender, EventArgs e)
{
   if (!ContainsChildForm(typeof(child2)))
   {
       child2 c = new child2();
       c.MdiParent = this;
       c.Show();
   }
}

private bool ContainsChildForm(Type t)
{
   for (int i = 0; i < this.MdiChildren.Length; i++)
   {
       if (t.IsInstanceOfType(this.MdiChildren[i]))
       {
           return true;
       }
   }
   return false;
}

JacquesDP6-Mar-06 18:03

6-Mar-06 18:03

DigitalKing wrote:
if (!ContainsChildForm(typeof(child1)))

Does not reconize ContainsChildForm

DigitalKing6-Mar-06 18:13

6-Mar-06 18:13

I posted the code for this function before, but here it is again:

private bool ContainsChildForm(Type t)
{
   for (int i = 0; i < this.MdiChildren.Length; i++)
   {
       if (t.IsInstanceOfType(this.MdiChildren[i]))
       {
           return true;
       }
   }
   return false;
}

JacquesDP6-Mar-06 18:49

6-Mar-06 18:49

That worked 100, but how do I get the focus back to that childform if it exists?

DigitalKing6-Mar-06 18:59

6-Mar-06 18:59

private void CreateUniqueChild(Type t)
{
   int index = GetChildIndex(t);
   if (index == -1)
   {
       Form f = (Form)Activator.CreateInstance(t);
       f.MdiParent = this;
       f.Show();
   }
   else
   {
       this.MdiChildren[index].Focus();
   }
}

private int GetChildIndex(Type t)
{
   for (int i = 0; i < this.MdiChildren.Length; i++)
   {
       if (t.IsInstanceOfType(this.MdiChildren[i]))
       {
           return i;
       }
   }
   return -1;
}

private void newWindowType1ToolStripMenuItem_Click(object sender, EventArgs e)
{
   CreateUniqueChild(typeof(child1));
}

private void newWindowType2ToolStripMenuItem_Click(object sender, EventArgs e)
{
   CreateUniqueChild(typeof(child2));
}

PavanPabolu6-Nov-10 11:21

PavanPabolu

6-Nov-10 11:21

private void newWindowType2ToolStripMenuItem_Click(object sender, EventArgs e)<br />
{<br />
   if (!ContainsChildForm(typeof(child2)))<br />
   {<br />
       child2 c = new child2();<br />
       c.MdiParent = this;<br />
       c.Show();<br />
   }<br />
   else<br />
       c.Activate();<br />
}<br />
<br />
private bool ContainsChildForm(Type t)<br />
{<br />
   for (int i = 0; i < this.MdiChildren.Length; i++)<br />
   {<br />
       if (t.IsInstanceOfType(this.MdiChildren[i]))<br />
       {<br />
           return true;<br />
       }<br />
   }<br />
   return false;<br />
}

JacquesDP6-Mar-06 18:23

6-Mar-06 18:23

thanx a mil, works like a bomb

bind the datagrid

angelagke6-Mar-06 16:09

angelagke

6-Mar-06 16:09

after o add new column inside the datatable and bind into datagrid

DataColumn dc = new DataColumn();
DataTable dt = new DataTable();

dc.AutoIncrement = true;
dc.AutoIncrementSeed =1;
dc.Unique = true;
dc.ColumnName = "No";
dt.Columns.Add(dc);

SqlConnection objCN = new SqlConnection();
SqlCommand objCMD = new SqlCommand();
SqlDataAdapter objDA = new SqlDataAdapte();

objCN.ConnectionString = ConfigurationSettings.AppSettings["DSN"];
objCMD.Connection = objCN;
objCMD.CommandText = cmdText;
objCMD.CommandTimeout = 30;
objDA.SelectCommand = objCMD;

objCN.Open();
objDA.Fill(dt);
objCN.Close();

dGridRecord.DataSource = dt;
dGridRecord.DataBind();

but the new column 'No' i add in is not appear the increment number in my page after i run it.
wat value i need set data field for tis new column 'No' seem tis is auto generate number and no inside my database.

how i bind the 'No' column in my datagrid?? D'Oh! | :doh:

angela

goyal manish6-Mar-06 18:00

goyal manish

6-Mar-06 18:00

Hi
i think you have done well but you have missed to set autoincrement step in yours code. so add the following line of code just after the line where you have set the autoincrementseed.

dc.AutoIncrementStep = 1;

i htink yours problem will be solved. Smile | :)

angelagke6-Mar-06 18:13

angelagke

6-Mar-06 18:13

just now i set autoincrementseed,

dc.AutoIncrementStep = 1;

but the column 'No' also display nothing.....
i guess is my datagrid problem where i add a 'No'bound column but i not set d data field inside tat column... coz i dun know wat attribute to put in seem it no exit in my database, this column is auto generate number...

i also no sure whether i had bind the datatable to my datagrid correctly or not?? Confused | :confused:

angela

goyal manish6-Mar-06 23:56

goyal manish

6-Mar-06 23:56

have you made autogenerated column property of datagrid false? if you are using all the columns of datasource in datagrid then make it true. in that case you will not need to specify the column name for datagrid. Smile | :)

goyal manish7-Mar-06 0:03

goyal manish

7-Mar-06 0:03

hi
if you are using all columns of datasource in datagrid then make true autogenerae column property of datagrid and if u still dont get the value then try to get it in debug mode n check that in table you are getting all values or not.
In debug mode you will get the place of error.
Smile | :)

angelagke8-Mar-06 16:12

angelagke

8-Mar-06 16:12

i already success to generate my autogenerate collumn Smile | :)

thanks for your guide Wink | ;)

hav a nice week Rose | [Rose]

angela

cancel event

Dominic Farr6-Mar-06 16:07

Dominic Farr

6-Mar-06 16:07

I have a windows form with a button that I have set the DialogResult property.

The button also has a click event.

When the click event fires, my event methods displays an MessageBox with Yes or No buttons. (an 'are you sure' type message)

If the user clicks the No button I want to cancel closing of the window form event.

How I can I achieve this.

Thanks

Re: cancel event

DigitalKing6-Mar-06 17:32

6-Mar-06 17:32

private void button1_Click(object sender, EventArgs e)
{
    DialogResult dr = MessageBox.Show("Are you sure you want to close this window?", "Are you sure?", MessageBoxButtons.YesNo, MessageBoxIcon.Question);
    if (dr == DialogResult.Yes)
    {
        this.Close();
    }
    //if anything other than Yes is clicked (like No), then nothing will happen.
}

Re: cancel event

Dominic Farr7-Mar-06 7:25

Dominic Farr

7-Mar-06 7:25

The problem stems from button1 having it's DialogResult property set.

When button1 click event is fired, it executes button1_Click, displays the are you sure dialog and regardless of the result of the are you sure dialog will close the window form because it has a DialogResult set.

I was wondering if I could cancel this close window event depending on the result of the are you sure dialog.

I can simply not set the DialogResult property of button1, and set the DialogResult in the button1_Click event depending on the result of the are you sure dialog.

Regards.

Re: cancel event

DigitalKing7-Mar-06 17:54