两种实现表单验证的javascript方法
导语：表单验证如何实现呢?下面小编给大家介绍两种实现表单验证的javascript方法，大家可以参考阅读，更多详情请关注应届毕业生考试网。
第一种：js表单验证
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>注册-个人用户</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<script src="//cdn.bootcss.com/jquery/3.0.0-beta1/jquery.js"></script>
<style>
body {
font-family: Arial, "宋体", Lucida, Verdana, Helvetica, sans-serif;
font-size: 12px;
color: #333;
line-height: 150%;
background: #f2f2f2;
}
.hide{display:none;}
.focus,.error {
color: #e4393c;
line-height: 36px;
height: 36px;
position: absolute;
top: 0px;
width: 260px;
padding: 0 5px;
background: #FFEBEB;
border: 1px solid #ffbdbe;
}
.error span,.focus span {
padding: 5px 0;
line-height: 13px;
display: block;
}
.focus {
color: #666;
width: 260px;;
line-height: 36px;
background: #f7f7f7;
border: 1px solid #dddddd;
}
.regist {
width: 990px;
padding: 0;
margin: 0 auto;
zoom: 1;
}
.mc {
padding: 30px 0 20px;
border: solid #dddddd; border-width : 0px 1px 1px;
background: #FFF;
overflow: hidden;
zoom: 1;
border-width: 0px 1px 1px;
}
.form {
float: left;
width: 750px;
font-size: 12px;
}
.form label,.form input,.form select,.form textarea,.form button,.form .label {
float: left;
font-size: 12px;
}
.item {
padding-top: 9px;
height: 60px;
line-height: 34px;
position: relative;
z-index: 1;
}
.label {
float: left;
width: 190px;
text-align: right;
font-size: 14px;
color: #999;
padding-right: 10px;
}
.input {
float: left;
position: relative;
width: 270px;
overflow: visible;
}
.text {
float: none;
width: 275px;
height: 37px;
line-height: 32px;
border: 1px solid #cccccc;
font-size: 14px;
font-family: arial, "宋体";
overflow: hidden;
}
</style>
</head>
<body>
<p class="regist">
<p class="mc">
<form id="personRegForm" class="form" action="login.html" method="POST" onsubmit="return validateForm();">
<p class="item">
<span class="label">用户名：</span>
<p class="input">
<input type="text" id="username" name="username" class="text">
<label id="username_msg" class="hide"></label>
</p>
</p>
<p class="item">
<span class="label">请设置密码：</span>
<p class="input">
<input type="password" id="password" name="password" class="text">
<label id="pwd_msg" class="hide"></label>
</p>
</p>
<p class="item">
<span class="label">请确认密码：</span>
<p class="input">
<input type="password" id="pwdRepeat" name="pwdRepeat" class="text">
<label id="pwdRepeat_msg" class="hide"></label>
</p>
</p>
<p class="item">
<span class="label">验证邮箱：</span>
<p class="input">
<input type="text" id="mail" name="mail" class="text">
<label id="mail_msg" class="hide"></label>
</p>
</p>
<p class="item">
<span class="label"> </span>
<input type="submit" class="btn-img" id="registsubmit" value="立即注册" />
</p>
</form>
</p>
</p>
<script>
window.onload = function(){
// 1. 用户名
$("#username").focus(function(){
/* 获取焦点
var username_msg = $("#username_msg");
username_msg.text("4-20位字符，支持英文、数字及'-'、'_'组合");
username_msg.attr("class","focus");
*/
elemFocus("username_msg","4-20位字符，支持英文、数字及'-'、'_'组合");
}).blur(userValidator);
// 2. 密码
$("#password").focus(function(){
elemFocus("pwd_msg","6-20位字符，可使用字母、数字的组合");
}).blur(pwdValidator);
// 3. 确认密码
$("#pwdRepeat").focus(function(){
elemFocus("pwdRepeat_msg","6-20位字符，可使用字母、数字的'组合");
}).blur(pwdRepeatValidator);
// 4. Email
$("#mail").focus(function(){
elemFocus("mail_msg","完成验证后，可以使用该邮箱登录和找回密码");
}).blur(emailValidator);
}
// 定义函数 - 通用的信息提示
function elemFocus(eleId,text){
var ele_msg = $("#"+eleId);
ele_msg.text(text);
ele_msg.attr("class","focus");
}
// 定义验证用户名的函数
function userValidator(){
// 获取用户名输入的值
var value = $("#username").val();
// 获取用于显示提示信息的元素
var username_msg = $("#username_msg");
// 验证逻辑
if(value==""||value==null){
username_msg.text("用户名不能为空");
username_msg.attr("class","error");
return false;
}else if(value.length<4||value.length>20){
username_msg.text("用户名的长度不正确");
username_msg.attr("class","error");
return false;
}else if(!/^[a-zA-Z0-9-_]{4,20}$/.test(value)){
username_msg.text("用户名输入不正确");
username_msg.attr("class","error");
return false;
}
// 验证通过修改正确样式
if(!username_msg.hasClass("hide")){
username_msg.text("");
username_msg.attr("class","hide");
}
return true;
}
// 定义验证密码的函数
function pwdValidator(){
var value = $("#password").val();