C#

string strPrimary = (ComboBox)sender.SelectedText;

string strPrimary = column1DataGridViewTextBoxColumn.ToString();

string strPrimary = dataGridView1[e.ColumnIndex, e.RowIndex].Value.ToString();

Henry Minute wrote:

What you were getting before was something like "DataGridViewComboBoxColumn{something="ibbledibble"}", rather than "Test1". In other words the DataGridViewComboBoxColumn class ToString, rather than the content ToString

string strPrimary = column1DataGridViewTextBoxColumn.DisplayIndex.ToString();
                        Debug.WriteLine(strPrimary);

public void column1DataGridViewTextBoxColumn_SelectedIndexChanged(object sender, DataGridViewCellEventArgs e)

private void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
{
    ComboBox cb = e.Control as ComboBox;

    if (cb != null)
    {
        // first remove event handler to keep from attaching multiple:
        cb.SelectedIndexChanged -= cb_SelectedIndexChanged;
        // now attach the event handler
        cb.SelectedIndexChanged += cb_SelectedIndexChanged;
    }
}



void cb_SelectedIndexChanged(object sender, EventArgs e)
{
    MessageBox.Show("Selected index changed");
}

private void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
{
   ComboBox cb;

   switch (dataGrid.CurrentCell.ColumnIndex)
   {
       case 0:  // use the index for your comboboxcolumn
           cb = e.Control as ComboBox;
           if (cb != null)
           {
           // first remove event handler to keep from attaching multiple:
           cb.SelectedIndexChanged -= cb_SelectedIndexChanged;
           // now attach the event handler
           cb.SelectedIndexChanged += cb_SelectedIndexChanged;
           }
           break;
      case 3: // use the index for your second combo
           cb = e.Control as ComboBox;
           if (cb != null)
           {
           // first remove event handler to keep from attaching multiple:
           cb.SelectedIndexChanged -= cb_SecondSelectedIndexChanged;
           // now attach the event handler
           cb.SelectedIndexChanged += cb_SecondSelectedIndexChanged;
           }
           break;
   }

ComboBox cb = e.Control as ComboBox;

private void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
{
    if ((ComboBox)e.Control != null)
    {
        // first remove event handler to keep from attaching multiple:
        ((ComboBox)e.Control).SelectedIndexChanged -= cb_SelectedIndexChanged;
        // now attach the event handler
        ((ComboBox)e.Control).SelectedIndexChanged += cb_SelectedIndexChanged;
    }
}

ComboBox cb = e.Control as ComboBox;

if (cb != null)
{
    // first remove event handler to keep from attaching multiple:
    cb.SelectedIndexChanged -= column1DataGridViewTextBoxColumn_SelectedIndexChanged;
    // now attach the event handler
    cb.SelectedIndexChanged += column1DataGridViewTextBoxColumn_SelectedIndexChanged;
}

private void column1DataGridViewComboBox_SelectedIndexChanged(object sender, DataGridViewCellEventArgs e)
       {

           string strPrimary = dataGridView1[e.ColumnIndex, e.RowIndex].Value.ToString();
           Debug.WriteLine(strPrimary);
           if (strPrimary == "Test1")
           {

               //Build a list
               var dataSource = new List<Units>();
               dataSource.Add(new Units() { Unit = "blah1" });
               dataSource.Add(new Units() { Unit = "blah2" });
               dataSource.Add(new Units() { Unit = "blah3" });

               //Setup data binding
               this.column2DataGridViewComboBox.DataSource = dataSource;
               this.column2DataGridViewComboBox.DisplayMember = "Unit";

           }
       }



       private void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
       {
           ComboBox cb = e.Control as ComboBox;

           if (cb != null)
           {
               // first remove event handler to keep from attaching multiple:
               cb.SelectedIndexChanged -= column1DataGridViewComboBox_SelectedIndexChanged;
               // now attach the event handler
               cb.SelectedIndexChanged += column1DataGridViewComboBox_SelectedIndexChanged;
           }
       }

private void column1DataGridViewComboBox_SelectedIndexChanged(object sender, DataGridViewCellEventArgs e)

private void column1DataGridViewComboBox_SelectedIndexChanged(object sender, EventArgs e)

private void column1DataGridViewComboBox_SelectedIndexChanged(object sender, EventArgs e)
{
    ComboBox cb = sender as ComboBox;
    string someString = cb.SelectedItem;
    // OR
    int cbIndex = cb.SelectedIndex;  // and so on
}

private void column1DataGridViewComboBox_SelectedIndexChanged(object sender, EventArgs e)
{
    string someString = ((ComboBox)sender).SelectedItem;
    // OR
    int cbIndex = ((ComboBox)sender).SelectedIndex;  // and so on
}

private void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
            {            
                ComboBox cb = e.Control as ComboBox;
                if (cb != null)            
                {                
                    // first remove event handler to keep from attaching multiple:
                    cb.SelectedIndexChanged -= column1DataGridViewComboBox_SelectedIndexChanged;
                    // now attach the event handler  
                    cb.SelectedIndexChanged += column1DataGridViewComboBox_SelectedIndexChanged; 
                }        

mprice214 wrote:

Since DataGridViewEditingControlShowingEventArgs is handling the EditingControlShowing event and will be passing the arguments to the SelectedIndexChanged event handle

if (!cb.SelectedIndexChanged.List.Contains(column1DataGridViewComboBox_SelectedIndexChanged))
{
 cb.SelectedIndexChanged += column1DataGridViewComboBox_SelectedIndexChanged;
}

Henry Minute wrote:

I think that you have slightly misunderstood what is happening here.

mprice214 wrote:

also SelectedIndexChanged cannot access the control via DataGridViewCellEventArgs because the control is accessed via EditingControlShowing with the DataGridViewEditingControlShowingEventArgs class, correct?

private void column1DataGridViewComboBox_SelectedIndexChanged(object sender, EventArgs e)
        {

            ComboBox cb = sender as ComboBox;

         
            string strPrimary = cb.SelectedItem.ToString();
            Debug.WriteLine(strPrimary);

            var dataSource = new List<Units>();

            switch (strPrimary)
            {
                case "1":
                    
                //Build a list 
                
                dataSource.Add(new Units() { Unit = "blah1" });
                dataSource.Add(new Units() { Unit = "blah2" });
                dataSource.Add(new Units() { Unit = "blah3" });

                //Setup data binding 
                this.column2DataGridViewComboBox.DataSource = dataSource;
                this.column2DataGridViewComboBox.DisplayMember = "Unit";

                break;

                case "2":

                //Build a list 
                dataSource.Add(new Units() { Unit = "blah4" });
                dataSource.Add(new Units() { Unit = "blah5" });
                dataSource.Add(new Units() { Unit = "blah6" });

                //Setup data binding 
                this.column2DataGridViewComboBox.DataSource = dataSource;
                this.column2DataGridViewComboBox.DisplayMember = "Unit";

                break;

                case "3":

                //Build a list 
                dataSource.Add(new Units() { Unit = "blah7" });
                dataSource.Add(new Units() { Unit = "blah8" });
                dataSource.Add(new Units() { Unit = "blah9" });

                //Setup data binding 
                this.column2DataGridViewComboBox.DataSource = dataSource;
                this.column2DataGridViewComboBox.DisplayMember = "Unit";

                break;

            }
        }<pre>

Well, the problem of course as you know is that ComboBox cb points to the second comboBox once I select it.  In fact, once I select a value on the first comboBox and then select the second comboBox to select a value, debug.writeline gives me "WindowsFormsApplication1.Form1+Units" (although the 2nd comboBox does get populated with the appropriate list based upon the selection of the first comboBox).  If I use an integer instead of strPrimary and set it as cb.SelectedIndex, what I actually get from debug is the index of the selection of the list of the second comboBox (eg if blah5 is selected, I get an integer = 1) followed by an integer = 0 (I don't know why it is passing that second integer = 0  ??), which then causes the list to be regenerated to the items in case 0.  Since ComboBox cb points to the second comboBox, and it passes that second integer = 0, the only allowable entry into the second comboBox would be "blah1"

With all of this, it seems that either close or going about it all wrong, but I don't know enough to make that call.  I know that the control for each comboBox needs to be separated, but don't have the slightest notion how to do that.  You had mentioned that in a previous post, but in the EditingControlShowing handler.  As usual, any suggestions would be greatly appreciated.

private void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
{
   ComboBox cb;

   // switch (dataGrid.CurrentCell.ColumnIndex)   <===================================== silly! already have column in eventargs
   switch (e.Column)                              //<==============================Use this instead
   {
       case 0:  // use the index for your comboboxcolumn    <============ <big>V IMPORTANT</big> make sure that the 0: matches the index for your column
           cb = e.Control as ComboBox;
           if (cb != null)
           {
           // first remove event handler to keep from attaching multiple:
           cb.SelectedIndexChanged -= column1DataGridViewComboBox_SelectedIndexChanged;
           // now attach the event handler
           cb.SelectedIndexChanged += column1DataGridViewComboBox_SelectedIndexChanged;
           }
           break;
        // <================================== You do not need the part below since you only need it to apply to the first cbcolumn
      //case 3: // use the index for your second combo
        //   cb = e.Control as ComboBox;
          // if (cb != null)
           //{
           // first remove event handler to keep from attaching multiple:
         //  cb.SelectedIndexChanged -= cb_SecondSelectedIndexChanged;
           // now attach the event handler
          // cb.SelectedIndexChanged += cb_SecondSelectedIndexChanged;
           //}
           //break;
   }
}

private void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
{
   ComboBox cb;

   // replace the switch statement by an if statement
   if (e.Column == 0)  //<============ <big>V IMPORTANT</big> change the 0 (if necessary) to  match the index for your column
   {
           cb = e.Control as ComboBox;
           if (cb != null)
           {
           // first remove event handler to keep from attaching multiple:
           cb.SelectedIndexChanged -= column1DataGridViewComboBox_SelectedIndexChanged;
           // now attach the event handler
           cb.SelectedIndexChanged += column1DataGridViewComboBox_SelectedIndexChanged;
           }
    }
}