I have a ASP.NET textbox. On text change or move to a different control in the page, I want to check if textbox value ends with .zip, if not show a text message that .zip extension text is required. I have tried the below, but not sure how to get the ends with .zip and show message.
$('#<%=txtfilename.ClientID%>').change(function (e) {
var value = $(this).val();
});