Asp.net树状视图-单击同一节点时不会触发事件

Partial Class YourPageWithaAtreeView  
    Inherits System.Web.UI.Page  
Dim _blnSelectionChanged as Boolean = false



Protected Sub MyTree_SelectedNodeChanged(byval sender as object, byval e as eventargs) handles MyTree.SelectedNodeChanged  
   _blnSelectionChanged = true //The selection changed
End Sub
Protected Sub MyTree_PreRender(byval sender as object, byval e as eventargs) handles MyTree.PreRender
    if _blnSelectionChanged = false Then
      //Because the boolean is not true that means that 
      //the selected node didn\'t change
      //insert the code you want to execute when the user
      //clicks the already selected node
    end if
End Sub