[Solved] Selective Server Side call

[Hemangajit Dutta]

Hi,
        I am using a treeview where I need to do some server side validation when user unchecks a node. I am using the 

onnodecheck

 

event  to capture the checkbox check event in the server side. However the server side method is called and a postback happen when a user both checks or unchecks a node. Is there a way of triggering the server side call only when user unchecks the checkbox. I need to restrict the page from making postback when user checks it.

Kindly let me know a solution

Thanks and Regards
Hemangajit

[Shinu]

Hello Hemangajit,

Try the following approach by attaching the 'OnClientNodeChecking' event and canceling/preventing the server event based on condition.

JavaScript:

<script type="text/javascript">
var check = true;
function OnClientNodeChecking(sender, args) {

    if (!args.get_node().get_checked()&& check) {
        args.set_cancel(true);
        check = false;
        args.get_node().set_checked(true);
    }
}
</script>

-Shinu.

[Hemangajit Dutta]

HI Shinu,
                 Thanks. A strange problem is happening. I modified the code as per my application need. After I check the checkbox, it is not getting checked in the client side(The tick mark is not appearing. However when I made a postback, the nodes are checked at server side. I put an alert after commiting the changes, it says true. I am a bit puzzled. The version I am using is 2009.2.701.20

 

if (!args.get_node().get_checked())

 

{

 

var treeView = $find("<%=trTaxonomy.ClientID%>");

 

treeView.trackChanges();

args.get_node().set_checked(

true);

 

args.set_cancel(

true);

 

treeView.commitChanges();

 

alert(args.get_node().get_checked());

 

 

}

Thanks
Hemangajit

[Veselin Vasilev]

Hello Hemangajit Dutta,

Here is another solution:

<telerik:RadTreeView ID="RadTreeView1" runat="server" CheckBoxes="True"
    OnClientNodeChecked="onNodeChecked"
    onnodecheck="RadTreeView1_NodeCheck" Skin="Sitefinity">
    <Nodes>
        <telerik:RadTreeNode runat="server" Text="Root RadTreeNode1">
            <Nodes>
                <telerik:RadTreeNode runat="server" Text="Child RadTreeNode 1">
                </telerik:RadTreeNode>
                <telerik:RadTreeNode runat="server" Text="Child RadTreeNode 2">
                </telerik:RadTreeNode>
            </Nodes>
        </telerik:RadTreeNode>
        <telerik:RadTreeNode runat="server" Text="Root RadTreeNode3">
        </telerik:RadTreeNode>
    </Nodes>
</telerik:RadTreeView>

<script type="text/javascript">
    function onNodeChecked(sender, e) {
        var node = e.get_node();
        if (node.get_checked()) {
            sender._postBackOnCheck = false;
        }

        setTimeout(function() { sender._postBackOnCheck = true; }, 100);
    }
</script>

Kind regards,
Veselin Vasilev
the Telerik team

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