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<!DOCTYPE html> <html> <head> <script> onerror = handleErr; var txt = ""; function handleErr(msg, url, l) { txt = "There was an error on this page.\n\n"; txt += "Error: " + msg + "\n"; txt += "URL: " + url + "\n"; txt += "Line: " + l + "\n\n"; txt += "Click OK to continue.\n\n"; alert(txt); return true; } function message() { adddlert("Welcome guest!"); } </script> </head> <body> <input type="button" value="View message" onclick="message()" /> </body> <!-- Mirrored from www.w3schools.com/js/tryit.asp?filename=tryjs_onerror by HTTrack Website Copier/3.x [XR&CO'2014], Fri, 23 Jan 2015 07:24:34 GMT --> </html>
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