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Get value from asp:textbox client side.

osiris247 asked
Medium Priority
Last Modified: 2012-06-27

Ok, something i thought was easy has turned out not so much!

I am trying to get the value from an asp:textbox and without postback.
I have this.....
const string _AccountScript = @"
        <script language='javascript' type='text/javascript'>
            function AddAccount()
                var chrAccountName = document.getElementById('txtAccount').value;
                WinOpen('ToolsPopup.aspx?chrAccountName= + chrAccountName,290,520,'Aname');
                return false;
ClientScript.RegisterClientScriptBlock(GetType(), "AddAccount", _AccountScript);

in button properties i have AddAccount();
I have debugged as best i can and the getElementById is where it falls over.  I can set the var to a const string and it works fine??? My textbox is is without a doubt 'txtAccount' (correct case).

The error i get is 'Object Required'.

The second part....how can i stop the button posting back??
Watch Question

If you view the source HTML from your browser, can you confirm the textbox does have an id of "txtAccount"?

i.e. if you have a usercontrol with a textbox (id "txtAccount") in, and have that usercontrol on your webform, the actual ID it will render with will include a prefix to link the textbox to the usercontrol it's embedded in, hence why your JS may not find it

>> The second part....how can i stop the button posting back??
Use a normal HTML button


thanks...first part.  You were correct the id does have a long prefix. :)

second part.
Its not a button, its a custom control i have inherited from the ImageButton class.

Any ideas?
Ok, you can cancel the postback by adding "return false;" to the onclick event of the button.


<asp:button id="btnSomebutton" runat="server"/>

In code behind:
btnSomebutton.attributes.add("onclick", "alert('Test Message');return false;")

This example will display a javascript alert box, and then by having the "return false" afterwards, it will prevent a postback.

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