用原生JS写一个简单的表单验证功能，代码分为html部分和js部分，代码简单易懂，非常不错，具有参考借鉴价值，需要的朋友参考下
用原生JS写一个简单的表单验证
首先，是html部分
<p class="pAll">
<p id="titles">新用户注册</p>
<p id="contents">
<h3>基本信息</h3>
<hr width="95%" color="#f2f2f2"/>
<form action="#" onSubmit="return checkForm()">
<p id="form-itemGroup">
<label for="userName">用户名：</label>
<input type="text" id="userName" class="userName" onBlur="checkUserName()" oninput="checkUserName()">
<span class="default" id="nameErr">请输入至少3位的用户名</span>
</p>
<p id="form-itemGroup">
<label for="userPasword">密码：</label>
<input type="password" id="userPasword" class="userName" onBlur="checkPassword()" oninput="checkPassword()">
<span class="default" id="passwordErr">请输入4到8位的密码</span>
</p>
<p id="form-itemGroup">
<label for="userConfirmPasword">确认密码：</label>
<input type="password" id="userConfirmPasword" class="userName" onBlur="ConfirmPassword()" oninput="ConfirmPassword()">
<span class="default" id="conPasswordErr">请再输入一遍密码</span>
</p>
<p id="form-itemGroup">
<label for="userPhone">手机号码：</label>
<input type="text" id="userPhone" class="userName" onBlur="checkPhone()" oninput="checkPhone()">
<span class="default" id="phoneErr">请输入11位手机号码</span>
</p>
<p>
<button type="submit" class="pBtn">注册</button>
</p>
</form>
</p>
</p>接着，为其加上CSS样式
<style type="text/css">
.pAll{
width:800px;
font-family:'黑体';
margin:50px auto;
}
#titles{
font-weight:bold;
font-size:18px;
height:50px;
line-height:50px;
background:#FFF9F3;
text-align:center;
border:1px solid #CCC;;
}
#contents{
margin-top:20px;
background:#FFF9F3;
border:1px solid #CCC;;
}
#form-itemGroup{
padding:10px;
}
#form-itemGroup label{
display:inline-block;
width:100px;
height:32px;
line-height:32px;
color:#666;
text-align:right;
}
#form-itemGroup .userName{
width:200px;
height:40px;
line-height:40px;
border:1px solid #CCC;
}
#form-itemGroup .default{
width:200px;
height:32px;
line-height:32px;
color:#999;
}
#form-itemGroup .error{
height:32px;
line-height:32px;
color:#F00;
}
#form-itemGroup .success{
height:32px;
line-height:32px;
color:#096;
}
.pBtn{
margin-top:20px;
margin-left:200px;
width:100px;
height:32px;
line-height:32px;
background-color:#F93;
margin-bottom:10px;
color:#ffffff;
font-weight:bold;
border:none;
}
</style>最后是JS部分
<script type="text/javascript">
function checkForm(){
var nametip = checkUserName();
var passtip = checkPassword();
var conpasstip = ConfirmPassword();
var phonetip = checkPhone();
return nametip && passtip && conpasstip && phonetip;
}
//验证用户名
function checkUserName(){
var username = document.getElementById('userName');
var errname = document.getElementById('nameErr');
var pattern = /^\w{3,}$/; //用户名格式正则表达式：用户名要至少三位
if(username.value.length == 0){
errname.innerHTML="用户名不能为空"
errname.className="error"
return false;
}
if(!pattern.test(username.value)){
errname.innerHTML="用户名不合规范"
errname.className="error"
return false;
}
else{
errname.innerHTML="OK"
errname.className="success";
return true;
}
}
//验证密码
function checkPassword(){
var userpasswd = document.getElementById('userPasword');
var errPasswd = document.getElementById('passwordErr');
var pattern = /^\w{4,8}$/; //密码要在4-8位
if(!pattern.test(userpasswd.value)){
errPasswd.innerHTML="密码不合规范"
errPasswd.className="error"
return false;
}
else{
errPasswd.innerHTML="OK"
errPasswd.className="success";
return true;
}
}
//确认密码
function ConfirmPassword(){
var userpasswd = document.getElementById('userPasword');
var userConPassword = document.getElementById('userConfirmPasword');
var errConPasswd = document.getElementById('conPasswordErr');
if((userpasswd.value)!=(userConPassword.value) || userConPassword.value.length == 0){
errConPasswd.innerHTML="上下密码不一致"
errConPasswd.className="error"
return false;
}
else{
errConPasswd.innerHTML="OK"
errConPasswd.className="success";
return true;
}
}
//验证手机号
function checkPhone(){
var userphone = document.getElementById('userPhone');
var phonrErr = document.getElementById('phoneErr');
var pattern = /^1[34578]\d{9}$/; //验证手机号正则表达式
if(!pattern.test(userphone.value)){
phonrErr.innerHTML="手机号码不合规范"
phonrErr.className="error"
return false;
}
else{
phonrErr.innerHTML="OK"
phonrErr.className="success";
return true;
}
}
</script>好了，打开浏览器测试一下吧
填写数据，可以！
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