W3School TIY
编辑您的代码：
<html> <head> <script type="text/javascript"> var c=0 var t function timedCount() { document.getElementById('txt').value=c c=c+1 t=setTimeout("timedCount()",1000) } </script> </head> <body> <form> <input type="button" value="开始计时！" onClick="timedCount()"> <input type="text" id="txt"> </form> <p>请点击上面的按钮。输入框会从 0 开始一直进行计时。</p> </body> </html>
查看结果: