1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 2 <html xmlns="http://www.w3.org/1999/xhtml"> 3 <head> 4 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> 5 <title>验证是否为空</title> 6 <script type="text/javascript"> 7 function checkForm(yourinfo){ 8 if(yourinfo.namestring.value==""||yourinfo.namestring.value==null){ 9 alert("请输入你的名字"); 10 return(false); 11 } 12 else{ 13 return(true); 14 } 15 } 16 </script> 17 </head> 18 19 <body> 20 <form name="info" method="post" onSubmit="return checkForm(this);"> 21 <p>姓名：<input type="text" name="namestring" size="60"/></p> 22 <p><input type="submit" value="提交" /> <input type="reset" value="重置" /></p> 23 </form> 24 </body> 25 </html>