源代码:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Wfuyu教程(wfuyu.com)</title> </head> <head> </head> <body> <p id="demo"></p> <p>开启调试工具，在代码执行到第三行前会停止执行。</p> <script> var x = 15 * 5; debugger; document.getElementById("demo").innerHTML = x; </script> </body> </html>
运行结果：