Below code use error handling in js.
function
Navigate() {
try {
addlert("Welcome
guest!");
}
catch (err) {
txt =
"There was an error on this page.\n\n";
txt +=
"Error description: " + err.message +
"\n\n";
txt +=
"Click OK to continue.\n\n";
alert(txt);
}
}
</script>
<body>
<form id="form1" runat="server">
<div>
<%-- <asp
button type="button" onclick="alert('Welcome!')">Click Me!</button>--%>
<asp:Button ID="Button1" Text="Open Web site" OnClientClick="Navigate()" runat="server" />
</div>
</form>