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<script type="text/javascript">

    function onTxtDoubleClick() {

        var x = document.getElementById("<%= Button1.ClientID %>");
    if (x); else alert(x); }

Always return null .Please Hep me?

I am using this script on my usercontrol and the user control includes texbox and Button1. When I am adding this usercontrol in to my pages then problem occurs because document.getElementById("<%= Button1.ClientID %>"); retuns null because the Button ,Button1, dosent Exist in the page.Button1 exist in usercontrol
Updated 6-Aug-13 19:19pm
ZurdoDev 6-Aug-13 8:15am
Debug it and tell us what is happening.
Member 8390746 7-Aug-13 1:07am
I am using this script on a user control and when I am adding this user control in to my page then problem occurs. document.getElementById("<%= Button1.ClientID %>"); returns null because there is no button, Button1, in my page.
[no name] 6-Aug-13 8:46am
What is your purpose here?
ZurdoDev 7-Aug-13 7:25am
Why is Button1 not on your page?

When controls are in user controls and then placed on a page, the actual client ID has part of the usercontrol name in it to keep the IDs unique. Some of the solutions have pointed that out so you may be better off just finding what the actual ID is and using that.
Member 8390746 7-Aug-13 8:03am
My user control name is txtLOV and in debugg
var x =document.getElementById("<%= Button1.ClientID %>"); looks like
var x = document.getElementById("'txtLOV2_Button1'");
and x is null
ZurdoDev 7-Aug-13 8:18am
You'll have to view source. It is likely ctl001_txtLOV2_Button1.
[no name] 8-Aug-13 2:00am
Have you tried solution 2. I guess that is the reason you might be getting null.

Do you try this?
<html xmlns="">
<head  runat="server">
    <script type="text/javascript">
        function TextBoxDoubleClick() {
            alert("Double click detected.");
    <form id="form1"  runat="server">
        <asp:textbox id="TextBox1" ondblclick="TextBoxDoubleClick()" runat="server"></asp:textbox>
<script type="text/javascript">
    function onTxtDoubleClick() {
        var x = document.getElementById("buttonclientid");
    if (x); else alert(x); }

will work for you

Member 8390746 7-Aug-13 1:55am
It also return null
Dholakiya Ankit 7-Aug-13 2:08am
show me ur code pls....
use browser developer tools to find out if the id of the button is same as u have given and 'x' is not a boolean value so compare it with some value. hope this will help u

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