一个注册框 进行表单验证处理
如图
有简单的验证提示功能
代码思路也比较简单
输入框失去焦点时便检测，并进行处理
表单具有 onsubmit = "return check()"行为，处理验证情况
点击提交表单按钮时，进行最终的验证，达到是否通过表单提交的请求。
先是最基本的html+css部分
<style type="text/css">
body{margin:0;padding: 0;}
.login{position:relative;margin:100px auto;padding:50px 20px;width: 350px;height: 200px;border:1px solid #333;}
.login legend{font-weight: bold;color: green;text-align: center;}
.login label{display:inline-block;width:130px;text-align: right;}
.btn{height: 30px;width:100px;padding: 5px;border:0;background-color: #00dddd;font-weight: bold;cursor: pointer;float: right;}
input{height: 20px;width: 170px;}
.borderRed{border: 2px solid red;}
img{display: none;}
</style>
</head>
<body>
<div class="login">
<form name="form" method="post" action="register.php" onsubmit="return check()">
<legend>【Register】</legend>
<p><label for="name">UserName: </label>
<input type="text" id="name" >
<img src="./img/gou.png" width="20px" height="20px"></p>
<p><label for="password">Password: </label>
<input type="password" id="password" >
<img src="./img/gantan.png" width="20px" height="20px"></p>
<p><label for="R_password">Password Again: </label>
<input type="password" id="R_password" >
<img src="./img/gou.png" width="20px" height="20px"></p>
<p><label for="email">Email: </label>
<input type="text" id="email" >
<img src="./img/gou.png" width="20px" height="20px"></p>
<p><input type="submit" value="Register" class="btn"></p>
</form>
</div>
然后是js的class相关处理函数
function hasClass(obj,cls){ // 判断obj是否有此class
return obj.className.match(new RegExp('(\\s|^)' + cls + '(\\s|$)'));
}
function addClass(obj,cls){ //给 obj添加class
if(!this.hasClass(obj,cls)){
obj.className += " "+cls;
}
}
function removeClass(obj,cls){ //移除obj对应的class
if(hasClass(obj,cls)){
var reg = new RegExp('(\\s|^)' + cls + '(\\s|$)');
obj.className = obj.className.replace(reg," ");
}
}
然后是验证各个输入框的值
function checkName(name){ //验证name
if(name != ""){ //不为空则正确，当然也可以ajax异步获取服务器判断用户名不重复则正确
removeClass(ele.name,"borderRed"); //移除class
document.images[0].setAttribute("src","./img/gou.png"); //对应图标
document.images[0].style.display = "inline"; //显示
return true;
}else{ //name不符合
addClass(ele.name,"borderRed"); //添加class
document.images[0].setAttribute("src","./img/gantan.png"); //对应图标
document.images[0].style.display = "inline"; //显示
return false;
}
}
function checkPassw(passw1,passw2){ //验证密码
if(passw1 == "" || passw2 == "" || passw1 !== passw2){ //两次密码输入不为空且不等 不符合
addClass(ele.password,"borderRed");
addClass(ele.R_password,"borderRed");
document.images[1].setAttribute("src","./img/gantan.png");
document.images[1].style.display = "inline";
document.images[2].setAttribute("src","./img/gantan.png");
document.images[2].style.display = "inline";
return false;
}else{ //密码输入正确
removeClass(ele.password,"borderRed");
removeClass(ele.R_password,"borderRed");
document.images[1].setAttribute("src","./img/gou.png");
document.images[1].style.display = "inline";
document.images[2].setAttribute("src","./img/gou.png");
document.images[2].style.display = "inline";
return true;
}
}
function checkEmail(email){ //验证邮箱
var pattern = /^([\.a-zA-Z0-9_-])+@([a-zA-Z0-9_-])+(\.[a-zA-Z0-9_-])+/;
if(!pattern.test(email)){ //email格式不正确
addClass(ele.email,"borderRed");
document.images[3].setAttribute("src","./img/gantan.png");
document.images[3].style.display = "inline";
ele.email.select();
return false;
}else{ //格式正确
removeClass(ele.email,"borderRed");
document.images[3].setAttribute("src","./img/gou.png");
document.images[3].style.display = "inline";
return true;
}
}
然后为各个输入框添加监听事件：
var ele = { //存放各个input字段obj
name: document.getElementById("name"),
password: document.getElementById("password"),
R_password: document.getElementById("R_password"),
email: document.getElementById("email")
};
ele.name.onblur = function(){ //name失去焦点则检测
checkName(ele.name.value);
}
ele.password.onblur = function(){ //password失去焦点则检测
checkPassw(ele.password.value,ele.R_password.value);
}
ele.R_password.onblur = function(){ //R_password失去焦点则检测
checkPassw(ele.password.value,ele.R_password.value);
}
ele.email.onblur = function(){ //email失去焦点则检测
checkEmail(ele.email.value);
}
最后就是点击提交注册时调用的check()函数了
function check(){ //表单提交则验证开始
var ok = false;
var nameOk = false;
var emailOk = false;
var passwOk = false;
if(checkName(ele.name.value)){ nameOk = true; } //验证name
if(checkPassw(ele.password.value,ele.R_password.value)){ passwOk = true; } //验证password
if(checkEmail(ele.email.value)){ emailOk = true; } //验证email
if(nameOk && passwOk && emailOk){
alert("Tip: Register Success .."); //注册成功
//return true;
}
return false; //有误，注册失败
}
完整代码：
Register
以上所述就是本文的全部内容了，希望能够对大家学习javascript表单验证有所帮助。
