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<!DOCTYPE html> <html> <head> <script> onerror = handleErr; var txt = ""; function handleErr(msg, url, l) { txt = "此页面出错。\n\n"; txt += "错误：" + msg + "\n"; txt += "URL：" + url + "\n"; txt += "Line：" + l + "\n\n"; txt += "单击“确定”以继续。\n\n"; alert(txt); return true; } function message() { adddlert("欢迎访客！"); } </script> </head> <body> <input type="button" value="查看消息" onclick="message()" /> </body> </html>