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c#.netwinformstreeview

How do I set an image for some but not all nodes in a TreeView?

I have a TreeView windows forms control with an ImageList, and I want some of the nodes to display images, but the others to not have images.

I don't want a blank space where the image should be. I don't want an image that looks like the lines that the TreeView would draw if it didn't have an ImageList. How do I get it to draw images for some items and not others, without resorting to clumsy hacks like that?

Solution

  • I tried this once and I don't think it is possible.

    If you try to set both ImageKey and ImageIndex to "not set" values the control just defaults ImageIndex to 0. The following code:

    treeView.ImageKey = "Value";
Debug.WriteLine(treeView.ImageIndex);
treeView.ImageKey = null;
Debug.WriteLine(treeView.ImageIndex);
treeView.ImageIndex = -1;
Debug.WriteLine(treeView.ImageIndex);

    Produces output:

    -1
0
0

    This kind of tells you that the control developers wanted to make sure that there was always a default image. That just leaves you with the hack options I'm afraid.