Copying DropDownItems from one ToolStripDropDownItem to another

[Dewald]

Hi all, I have a ToolStripMenuItem in my MenuStrip. I've added a few ToolStripMenuItems as dropdown items at design time. Now I'd like to copy that list of dropdown items to a ToolStripDropDownButton at runtime but I seem to move the items from the ToolStripMenuItem to the ToolStripDropDownButton, not duplicate it. Here is the code I'm using:

ToolStripItem[] newitems = new ToolStripItem[myToolStripMenuItem.DropDownItems.Count];
myToolStripMenuItem.DropDownItems.CopyTo(newitems, 0);
myToolStripDropDownButton.DropDownItems.AddRange(newitems);

But the problem is that as soon as the last line executes the DropDownItems collection for the ToolStripMenuItem becomes empty. Does anyone have advice for me? Thanks in advance.

[musefan]

I think your issue is that your array is essentially storing references of each button - so your last line is in effect adding the exact same buttons (and will automatically become a "move") What you should do is... - Iterate the existing list of items - create new items based on the existing ones - add the new one to where you want them this should provide a "copy" for you

foreach(ToolStripItem item in myToolStripMenuItem.DropDownItem){
ToolStripItem newItem = new ToolStripItem();
//set anything you want the same, maybe there is a function for duplication I don't know
myToolStripDropDownButton.DropDownItems.Add(newItem);
}

return 5;

[Dewald]

First of all, the ToolStripItem() constructor is protected so your first line in the foreach loop is already going to cause a problem. Secondly, it's that comment line of yours that is the big headache. It means I have to copy the event handler, the tooltip text and everything. Is it a fact that a ToolStripItem can belong to only one DropDownItem collection?

[musefan]

The code was more for a idea than actual use - I have not worked with them for a while and forget the actual usage but I have created them dynamically is the past so I know you can create an instance somehow. Again, its been a while so I didn't know if there was a 'clone' type of function perhaps. But considering it is a button surely you will only need to copy a few key values such as Text, Icon (if any) and the Click eventHandler. ToolStripItem is a Control, and a Control can only have one parent Control - Basically what you have inadvertently ended up doing is changing the parent control - this is why it appears to "Move" (I don't know much about how this happens 'behind the scenes' thou)

return 5;

[musefan]

Had a little play now.. are your items all the same type? i.e. ToolStripButton as you can create all those controls. This is pretty messy but just an idea of what I was playing with...

foreach (ToolStripItem item in toolStripDropDownButton1.DropDownItems)
{
ToolStripItem newItem = new ToolStripMenuItem();
if (item is ToolStripComboBox)
newItem = new ToolStripComboBox();
else if (item is ToolStripTextBox)
newItem = new ToolStripTextBox();
newItem.Text = item.Text;
toolStripDropDownButton2.DropDownItems.Add(newItem);
}

return 5;