前端开发避坑-form表单action和submit提交与ajax异步提交冲突引起的故障解决！
近期在开发网站前端的时候，始终出现2次请求。困扰了很久。查询了网上的解决办法。发现，根源是因为，我的form表单里增加了一个action。虽然里面是空的，但是依然会在点击submit格式的按钮时，触发一次请求。这就引起了一种怪异的现象。
虽然ajax执行了成功！数据库执行了追加数据操作。但是页面始终停留在当前地址。
非常怪异，实际上，大家去掉form表单内的action，改一下submit,改成button模式，就可以恢复正常了。
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8">
<title>用户注册-积德寺-菩提佛堂app-网页版</title>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="keywords" content="许愿祈福,祈福网站"/>
<meta name="description" content="欢迎注册菩提佛堂app账号信息，可以参加线上共修活动！"/>
<link th:href="@{/static/css/mycommon.css}" rel="stylesheet" type="text/css">
<link th:href="@{/static/css/login.css}" rel="stylesheet" type="text/css">
<script th:src="@{/static/js/jquery.js}"></script>
<style>
.qifu_main {
margin:10px auto;
padding:14px;
border: 1px solid #99CC00;
border-radius: 8px;
background: rgba(235, 179, 22, 0.8);
text-align: center;
font-size: 1.0em;
width: 80%;
height:auto;
}
.qifu_main .form_register {
width: auto;
height: auto;
}
.qifu_main p img{
width: 80%;
}
.qifu_main .form_register .item {
margin: 8px auto;
padding-bottom: 12px;
text-align: left;
width: auto;
height: auto;
}
.qifu_main .form_register button {
display: block;
width: 100px;
height: 30px;
border-radius: 10px;
background-color: #ffb100;
font-size: 1.0em;
color: #FFFFFF;
margin: 5px auto;
}
.qifu_main .form_register .item select{
width: 30%;
height: 26px;
}
.qifu_main .form_register .item input{
width: 100%;
height: 26px;
}
.qifu_main .form_register .item .icon-input{
display: inline-block;
height: 30px;
line-height: 30px;
}
.qifu_main .form_register .item label img{
width: 30px;
height: auto;
}
</style>
</head>
<body>
<div th:replace="header :: top"></div>
<!--开始注册-->
<div class="qifu_main">
<p>欢迎注册会员</p>
<form id="form_register" class="form_register">
<div class="item">
<label for="uname"><img th:src="@{/static/images/icon-lianhua.png}">名字:</label>
<input type="text" required id="uname" name="username" minlength="2" maxlength="10" placeholder="您的名字不超过10个字">
<span class="msg-default hidden" id="namespan">用户名长度最小为2,最大为10</span>
</div>
<div class="item">
<label for="upassword"><img th:src="@{/static/images/icon-lianhua.png}">密码:</label>
<input type="password" required id="upassword" minlength="6" maxlength="10" name="password" placeholder="请设置您的密码">
<span class="msg-default hidden">密码长度在6到10位之间</span>
</div>
<div class="item">
<label for="upwdconfirm"><img th:src="@{/static/images/icon-lianhua.png}">验证密码:</label>
<input type="password" required id="upwdconfirm" name="upwdconfirm" minlength="6" maxlength="10" placeholder="请再次输入密码">
<span class="msg-default hidden">密码长度在6到10位之间</span>
</div>
<div class="item">
<label for="phone"><img th:src="@{/static/images/icon-lianhua.png}">手机:</label>
<input type="phone" required id="phone" name="phone" maxlength="11" pattern="(\d{11})|^((\d{7,8})|(\d{4}|\d{3})-(\d{7,8})|(\d{4}|\d{3})-(\d{7,8})-(\d{4}|\d{3}|\d{2}|\d{1})|(\d{7,8})-(\d{4}|\d{3}|\d{2}|\d{1}))$" placeholder="请输入手机号码">
<span class="msg-default hidden" id="phonespan">手机长度最大50位</span>
</div>
<div class="item">
<label for="email"><img th:src="@{/static/images/icon-lianhua.png}">邮箱:</label>
<input type="email" required id="email" name="email" maxlength="100" placeholder="请输入邮箱">
<span class="msg-default hidden" id="emailspan">邮箱长度最大100位</span>
</div>
<div class="item">
<button type="button" id="btnRegister" >提交</button>
<button type="reset" >重置</button>
</div>
</form>
</div>
<!--结束注册-->
<div th:replace="footer :: footer"></div>
<script>
/*1.对用户名进行验证*/
//当对象失去焦点触发验证流程
uname.onblur = function(){
if(this.validity.valueMissing){
this.nextElementSibling.innerHTML = '用户名不能为空';
this.nextElementSibling.className = 'msg-error';
this.setCustomValidity('用户名不能为空');
}else if(this.validity.tooShort){
this.nextElementSibling.innerHTML = '用户名不能少于2位';
this.nextElementSibling.className = 'msg-error';
this.setCustomValidity('用户名不能少于2位');
}else {
this.nextElementSibling.innerHTML = '用户名格式正确';
this.nextElementSibling.className = 'msg-success';
this.setCustomValidity('');
var data =$("#uname").val();
if(!data){ //用户没有输入任何内容
return;
}
/**发起异步GET请求，询问服务器用户名是否已经存在**/
$.ajax({
url:"../user/checkName",
data:"username="+$("#uname").val(),
type:"get",
dataType:"json",
success:function(obj){
$("#namespan").html(obj.message);//显示服务器的响应信息
if(obj.state==0){
$("#namespan").attr("class","msg-error");
}else{
$("#namespan").attr("class","msg-success");
}
}
});
}
}
uname.onfocus = function(){
this.nextElementSibling.innerHTML = '用户名长度在2到10位之间';
this.nextElementSibling.className = 'msg-default';
}
upassword.onfocus = function(){
this.nextElementSibling.innerHTML = '密码长度在6到10位之间';
this.nextElementSibling.className = 'msg-default';
}
upassword.onblur = function(){
if(this.validity.valueMissing){
this.nextElementSibling.innerHTML = '密码不能为空';
this.nextElementSibling.className = 'msg-error';
this.setCustomValidity('密码不能为空');
}else if(this.validity.tooShort){
this.nextElementSibling.innerHTML = '密码长度在尽量别少于6位';
this.nextElementSibling.className = 'msg-error';
this.setCustomValidity('密码长度在尽量别少于6位');
}else {
this.nextElementSibling.innerHTML = '密码格式正确';
this.nextElementSibling.className = 'msg-success';
this.setCustomValidity('');
}
}
upwdconfirm.onfocus = function(){
this.nextElementSibling.innerHTML = '密码长度在6到10位之间';
this.nextElementSibling.className = 'msg-default';
}
//当确认密码输入框失去焦点时触发验证。
upwdconfirm.onblur = function(){
if(this.validity.valueMissing){
this.nextElementSibling.innerHTML = '密码不能为空';
this.nextElementSibling.className = 'msg-error';
this.setCustomValidity('密码不能为空');
}else if(this.validity.tooShort){
this.nextElementSibling.innerHTML = '密码长度在尽量别少于6位';
this.nextElementSibling.className = 'msg-error';
this.setCustomValidity('密码长度在尽量别少于6位');
}else {
this.nextElementSibling.innerHTML = '密码格式正确';
this.nextElementSibling.className = 'msg-success';
this.setCustomValidity('');
var pwd1 =$("#upassword").val();
var pwd2 =$("#upwdconfirm").val();
if(pwd1!=pwd2){
this.nextElementSibling.innerHTML = '两次输入密码不一致';
this.nextElementSibling.className = 'msg-error';
this.setCustomValidity('密码长度在尽量别少于6位');
}else{
this.nextElementSibling.innerHTML = '两次输入密码一致';
this.nextElementSibling.className = 'msg-success';
this.setCustomValidity('');
}
}
}
/*3.对邮箱地址进行验证*/
email.onblur = function(){
if(this.validity.valueMissing){
this.nextElementSibling.innerHTML = '邮箱不能为空';
this.nextElementSibling.className = 'msg-error';
this.setCustomValidity('邮箱不能为空');
}else if(this.validity.typeMismatch){
this.nextElementSibling.innerHTML = '邮箱格式不正确';
this.nextElementSibling.className = 'msg-error';
this.setCustomValidity('邮箱格式不正确');
}else {
this.nextElementSibling.innerHTML = '邮箱格式正确';
this.nextElementSibling.className = 'msg-success';
this.setCustomValidity('');
var data =document.getElementById("email").value;
if(!data){ //用户没有输入任何内容
return;
}
/**发起异步GET请求，询问服务器邮箱是否已经存在**/
$.ajax({
url:"../user/checkEmail",
data:"email="+$("#email").val(),
type:"get",
dataType:"json",
success:function(obj){
$("#emailspan").html(obj.message);
if(obj.state==0){
$("#emailspan").attr("class","msg-error");
}else{
$("#emailspan").attr("class","msg-success");
}
}
});
}
}
email.onfocus = function(){
this.nextElementSibling.innerHTML = '请输入合法的邮箱地址';
this.nextElementSibling.className = 'msg-default';
}
/*3.对手机号进行验证*/
phone.onblur = function(){
if(this.validity.valueMissing){
this.nextElementSibling.innerHTML = '手机号不能为空';
this.nextElementSibling.className = 'msg-error';
this.setCustomValidity('手机号不能为空');
}else if(this.validity.patternMismatch){
this.nextElementSibling.innerHTML = '手机号格式不正确';
this.nextElementSibling.className = 'msg-error';
this.setCustomValidity('手机号格式不正确');
}else {
this.nextElementSibling.innerHTML = '手机号格式正确';
this.nextElementSibling.className = 'msg-success';
this.setCustomValidity('');
var data =document.getElementById("phone").value;
if(!data){ //用户没有输入任何内容
return;
}
/**发起异步GET请求，询问服务器用户名是否已经存在**/
$.ajax({
url:"../user/checkPhone",
data:"phone="+$("#phone").val(),
type:"get",
dataType:"json",
success:function(obj){
$("#phonespan").html(obj.message);
if(obj.state==0){
$("#phonespan").attr("class","msg-error");
}else{
$("#phonespan").attr("class","msg-success");
}
}
});
}
}
phone.onfocus = function(){
this.nextElementSibling.innerHTML = '请输入合法的手机号';
this.nextElementSibling.className = 'msg-default';
}
</script>
<script>
$('#btnRegister').click(function(){
var lengths=0;
$('.item').each(function(){
if($(this).find('span').hasClass('msg-success')){
lengths++;
}
});
//异步注册提交
if(lengths==5){
$.ajax({
url:"../user/register",
data:$("#form_register").serialize(),//相当于表单内的提交表单值集合。必须使用到name
type:"post",
dataType:"json",
success:function(obj){
if(obj.state==0){
console.log(obj.state)
$("#namespan").html(obj.message)
$("#namespan").attr("class","msg-error")
}else if(obj.state==1){
console.log(obj.state)
window.location = "../user/showLogin"
}
},
error:function (obj){
$("#namespan").html(obj.message)
$("#namespan").attr("class","msg-error")
}
});
}
})
</script>
</body>
</html>如图所示，这个就是，我修改后的代码，里面button，之前是submit.form的内容页删掉了action.