how make a textbox enabled false without postbac k

[Patrick.O.Ige]

I have a textbox and a submit button on a page,
I want the user to type in some characters before i enable or make the
submit button visible
<asp:TextBox id="txt" autopostback="true" runat="server" Width="70%"
Rows="4" TextMode="MultiLine"></asp:TextBox>


I used the ontextChnaged event

private void onchange(object sender, System.EventArgs e)
{
if (txtEquivalentRequirement.Text.Length > 0)
{
btnUpdate.Enabled = true;
}
else
{
btnUpdate.Enabled = false;
}

}

But this has to do a postback.
Is there a way i can do this without postback
Any ideas

 

[Ward Bekker]

Hi Patrick,

You need to do it client side using Javascript.

--
Ward Bekker
"Asp.Net Discussions for the Professional Developer"
http://www.dotnettaxi.com

"Free .Net 2.0 C# to/from VB.Net Code Converter"
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[Mark Rae]

Is there a way i can do this without postback

This is fairly standard DHTML with client-side JavaScript...

 

[Patrick.O.Ige]

Yes i know i should be able to use js for that
But any samples ? if not then i would have to bring up something
Thx

 

[Mark Rae]

Yes i know i should be able to use js for that
But any samples ? if not then i would have to bring up something

Tsk! Tsk! Patrick...

<form id="frmDefault" method="post" runat="server">
<input type=text id=txtInput
onkeyup="document.getElementById('cmdButton').disabled =
(document.getElementById('txtInput').value.length == 0);">
<input type=button id=cmdButton value="Test">
</form>

 

[Bruce Barker]

note: if clientscript disables the control, the browser will not post it, so
the server will see the value.

-- bruce (sqlwork.com)

 

[Mark Rae]

note: if clientscript disables the control, the browser will not post it,
so the server will see the value.

Er...

 

[Rote Rote]

Mark,
Tsk.. Er..
Patrick