Assign value to textbox in javascript

It simply means that the element was not found. If its id value is "txtSearch" (check it up, should be id="txtSearch", and see how it looks in raw HTML on the client side, using "View Page Source"), the jQuery selector must be written as:

myElement = $("#txtSearch");
myElement.value = "hai";

One possible bug could be wrong id due to wrong use of ASP.NET ClientID. Check it up:
http://msdn.microsoft.com/en-us/library/system.web.ui.control.clientid.aspx[^],
http://msdn.microsoft.com/en-us/library/system.web.ui.control.clientidmode.aspx[^],
http://weblogs.asp.net/asptest/archive/2009/01/06/asp-net-4-0-clientid-overview.aspx[^].

—SA

Check this out hope it may help you,

<script type="text/javascript">
        function OnButtonClick() {
            var textcontrol = document.getElementById("txtname");
            textcontrol.value = "Arun";
        }

    </script>


<pre lang="HTML">

 <input type="text" id="txtname" />
    <input type="button" id="btnsubmit" onclick="OnButtonClick()" value="Submit" />

visit here.....


http://weblogs.asp.net/jalpeshpvadgama/archive/2011/09/08/jquery-and-asp-net-set-and-get-value-of-server-control.aspx[^]

or

how to assign function value to textbox in asp.net[^]

You can use like this

document.getElementById('txtSearch').value = "Set Value To textbox using javascript";

You can also use Jquery to set textbox value.

$("#txtSearch").val('Set Value To textbox using Jquery');