many have asked this before, look for a javascript solution thru google

"How can I disable enterkey in a form. "
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Try using some javascript.
I added it to my Base page that I inherit from and inject it to each child
page.
(As a bonus you get to set the initial focus for any control)

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Add code like this to any child page where you want to set focus to a
control or kill the enter key:

Public Sub New()
   MyBase.New()

  'set the focus to the UserID text box:
  InitialFocus = txtUserId

   'Do Not kill the Enter key on this page
   Me.killEnterKey = False

   'Kill the Enter key on this page
   'Me.killEnterKey = True

 End Sub

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Add this code to your javascript library which is loaded for each page:

function NetscapeEventHandler_KeyDown(e) {
 if (e.which == 13 && e.target.type != 'textarea' && e.target.type !=
'submit') { return false; }
 return true;
}

function MicrosoftEventHandler_KeyDown() {
 if (event.keyCode == 13 && event.srcElement.type != 'textarea' &&
event.srcElement.type != 'submit')
   return false;
 return true;
}

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Add this to the top of your Base page:

Public InitialFocus As Control
Protected KillEnterKey As Boolean = True

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Protected Overridable Sub Page_PreRender(ByVal sender As Object, ByVal e As
EventArgs)

Dim sb As New StringBuilder

   '-- Focus
   sb.Append("<script language='javascript'>")
   If Not InitialFocus Is Nothing Then
     sb.Append("document.getElementById('" & InitialFocus.ClientID &
"').focus();")
   End If

   '-- Append to the Browser Title set on an instance level

   'Code to call the Enter button kill javascript in library
   If KillEnterKey = True Then
     sb.Append("var nav = window.Event ? true : false;")
     sb.Append("if (nav) {")
     sb.Append("window.captureEvents(Event.KEYDOWN);")
     sb.Append("window.onkeydown = NetscapeEventHandler_KeyDown;")
     sb.Append("} else {")
     sb.Append("document.onkeydown = MicrosoftEventHandler_KeyDown;")
     sb.Append("}")
   End If

   sb.Append("</script>")
   RegisterStartupScript("My JScript", sb.ToString())

End Sub

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