I have a HTML control Inputbox:
<INPUT type="text" onkeyup="chkText(tester.value)" id="tester">

I want to access it through my codepage when I press a button


PrivateSub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

Dim strMessage As HtmlInputText
strMessage = Me.tester
Dim strScript AsString = "<script language=JavaScript>alert('" & strMessage.Value & "');</script>"
If (Not Page.IsStartupScriptRegistered("clientScript")) Then
Page.RegisterStartupScript("clientScript", strScript)
EndIf

EndSub

the error I get is:
Object reference not set to an instance of an object.

I want to keep the textbox client side validation because I check on every keyup. Is there any way to grab the text from the inputbox and use.

Thanks
Bob