源代码:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Wfuyu教程(wfuyu.com)</title> <script> function validateForm(){ var x=document.forms["myForm"]["fname"].value; if (x==null || x==""){ alert("姓必须填写"); return false; } } </script> </head> <body> <form name="myForm" action="/statics/demosource/demo-form.php" onsubmit="return validateForm()" method="post"> 姓: <input type="text" name="fname"> <input type="submit" value="提交"> </form> </body> </html>
运行结果：