js校验表单后提交表单的三种方法总结

第一种：

复制代码
代码如下:

<script
type="text/javascript">
         function check(form) {

if(form.userId.value=='') {
               
alert("请输入用户帐号!");
                form.userId.focus();
               
return false;
           }
      
if(form.password.value==''){
               
alert("请输入登录密码!");
                form.password.focus();
               
return false;
         }
         return true;
        
}
</script>

<form action="login.do?act=login" method="post">
用户帐号
  <input
type=text name="userId" size="18" value="" >
<br>
 登录密码     

<input type="password" name="password" size="19" value=""/>     

 <input type=submit name="submit1" value="登陆" onclick="return
check(this.form)">

</form>

第二种

复制代码
代码如下:

<script
type="text/javascript">
         function check(form) {

if(form.userId.value=='') {
               
alert("请输入用户帐号!");
                form.userId.focus();
               
return false;
           }
      
if(form.password.value==''){
               
alert("请输入登录密码!");
                form.password.focus();
               
return false;
         }
         return true;
        
}
</script>

<form action="login.do?act=login" method="post" onsubmit="return
check(this)">
用户帐号
  <input type=text name="userId" size="18"
value="" >
<br>
 登录密码     
<input type="password"
name="password" size="19" value=""/>     
 <input type=submit
name="submit1" value="登陆">

</form>

第三种：

复制代码
代码如下:

<script
type="text/javascript">
         function check(form) {

if(form.userId.value=='') {
               
alert("请输入用户帐号!");
                form.userId.focus();
               
return false;
           }
      
if(form.password.value==''){
               
alert("请输入登录密码!");
                form.password.focus();
               
return false;
         }

document.myform.submit();
}
</script>

<form action="login.do?act=login" name="myform"
method="post">
用户帐号
  <input type=text name="userId" size="18"
value="" >
<br>
 登录密码     
<input type="password"
name="password" size="19" value=""/>     
<input type=button
name="submit1" value="登陆" onclick="check(this.form)">

</form>