Checked Change event of tree view is not working

Question

I am working with Treeview control and I am using the following code

  <asp:TreeView ID="tvCategories" ShowCheckBox="False" Style="font-family: Trebuchet MS;
                                    margin-top: 5px; margin-bottom: 5px; margin-left: 20px; color: Black; font-size: 12px"
                                    runat="server" ShowLines="true" NodeIndent="5" OnTreeNodeCheckChanged="tvCategories_TreeNodeCheckChanged"
                                    OnSelectedNodeChanged="tvCategories_SelectedNodeChanged">
                                    <LeafNodeStyle ForeColor="#555555" />
                                    <ParentNodeStyle ForeColor="Black" />
                                    <RootNodeStyle ForeColor="Black" />
                                </asp:TreeView>

Both the OnTreeNodeCheckChanged and OnSelectedNodeChanged are not working and the AutoPostBack property is not available for Treeview.

Please help me out with this issue. Thanks

Answer 1

You need use javascript to make the page postback, then the treenodecheckchanged event can be fired.

like below, you should add the code of bolder to make the page postback.:

 <script language="javascript" type="text/javascript">
     function postBack()
 {
     var element = window.event.srcElement;
     if (element .tagName == "INPUT" && element.type == "checkbox")
     {
        __doPostBack("","");
     } 
 }

</script>

Add the above javascript code in the head section of the page.

onclick="javascript:postBack()"  

Answer 2

There is no AutoPostBack property for TreeView.

As per the MSDN:

The TreeNodeCheckChanged event is raised when a check box in the TreeView control changes state between posts to the server. This allows you to provide an event-handling method that performs a custom routine, such as updating a database or the displayed content, whenever this event occurs.

You can try javascript to postback the page by adding the onclick event.

Reference: PostBack on selecting checkbox of treeview