diagram.view.selectionlist is giving first last as threw some exception

I am using essential Diagram control and some nodes.I was trying to get the selection list of nodes from diagram on mouseclick on that node.First click on node gave me the selection list with nodes.But when I clicked again on the node it gave me Argument out of range exception exception like....
"Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index". Screenshot attached
Why this selection list works only once?Can anyone pls help me?

/Sebastain

Hi Aida,

In the method, just type the following "IF condition clause":

NodeCollection nd = this.diagram1.View.SelectionList;
if(!nd.IsEmpty)
if (nd.First is Node)
{
MessageBox.Show("Test");
}

Let me know if you need any further clarification in this regard, Thanks!

Happy coding!

- Ajeet