RadInputManager OnValidation

[Babak]

Hi.
I'm using RadInputManager to Validate my Controls .
But now I have a problem , I'm gonna use radinputmanager to validate a textbox width specific javascript method . I wrote the below code, but my button do post back . I want to stop post back before validating the textbox .
How can I do this  ?

  <telerik:RadScriptBlock ID="RadScriptBlock1" runat="server">
            <script type="text/javascript">
                function onValidating(sender, args) {
                    var nationalCode = $get(sender.get_targetControlIDs()[0]);
                    console.log(nationalCode.value);
                    if (!checkCodeMeli(nationalCode.value)) {
                       alert('the code is wrong');
                        nationalCode.focus();
                        return false;
                    }
                    else {
                        alert('The code is write ')
                        return true;
                    }
                }
                function pageLoad() {
                    window.$ = jQuery = $telerik.$;
                }

function checkCodeMeli(code) {
    var L = code.length;
    if (L < 8 || parseInt(code, 10) == 0) return false;
    code = ('0000' + code).substr(L + 4 - 10);
    if (parseInt(code.substr(3, 6), 10) == 0) return false;
    var c = parseInt(code.substr(9, 1), 10);
    var s = 0;
    for (var i = 0; i < 9; i++)
        s += parseInt(code.substr(i, 1), 10) * (10 - i);
    s = s % 11;
    return (s < 2 && c == s) || (s >= 2 && c == (11 - s));
    return true;
}
            </script>
        </telerik:RadScriptBlock>


         <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
        <asp:Button ID="btn" runat="server" />

        <telerik:RadInputManager ID="RadInputManager1" runat="server">
            <telerik:TextBoxSetting InitializeOnClient="true">
                <TargetControls>
                    <telerik:TargetInput ControlID="TextBox1" />
                </TargetControls>
                <ClientEvents OnValidating="onValidating" />
            </telerik:TextBoxSetting>
        </telerik:RadInputManager>

[Viktor Tachev]

Hello,

I tested the code you have provided and validation was performed as expected when a value was entered in the TextBox control. Postback was triggered only if the input was empty when the Button was clicked.

On order to prevent this scenario you could set the Validation-IsRequired property of the TextBoxSetting to true. This way a postback will be triggered only if there is a valid value entered in the TextBox control.

The markup for RadInputManager would look like below:

<telerik:RadInputManager ID="RadInputManager1" runat="server">
    <telerik:TextBoxSetting InitializeOnClient="true" Validation-IsRequired="true">
        <TargetControls>
            <telerik:TargetInput ControlID="TextBox1" />
        </TargetControls>
        <ClientEvents OnValidating="onValidating" />
    </telerik:TextBoxSetting>
</telerik:RadInputManager>

Regards,
Viktor Tachev
Telerik