Question

I am using the ASP.net ASP:Login, and i want to call a javascript function if login fails.

How can I accomplish this?

Answer 1

You can have a javascript function all ready on page, or you can add them later when the login fail. So first capture the login fail…

on your login module you add the event

<asp:Login OnLoginError="OnLoginError"  ... >

on code behind ether you open the javascript, ether you register a new one.

protected void OnLoginError(object sender, EventArgs e)
{
  // this
  txtMsg.Visible = true;

  // OR this
  Page.ClientScript.RegisterStartupScript(
               page.GetType(), "MsgFail", "alert('Login fail');", true);
}

Let say that you have a javasscript like this one for the first case.

<asp:literal run="server" id="txtMsg" EnableViewState="false" visible="false">
<script>
  alert("login fails");
</script>
</asp:literal>