前端页面：
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="Generator" content="EditPlus®">
<meta name="Author" content="">
<meta name="Keywords" content="">
<meta name="Description" content="">
<title>formdata对象封装表单数据</title>
<script type="text/javaScript">
function send(){
var xhr=new XMLHttpRequest();
xhr.open('POST','./01.php',true);//异步传输
xhr.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
var fm=document.getElementsByTagName('form')[0];
var fd=new FormData(fm);
xhr.onreadystatechange=function(){
if(this.readyState==4){
document.getElementById('username').innerHTML=xhr.responseText;
}
}
fd.append('act','zhuce');
xhr.send(fd);
}
</script>
</head>
<body>
<form action="./01.php" method="post">
<p>用户名：<input type="text" name="username"/><span id="username"></span></p>
<p>密码：<input type="password" name="pwd"/></p>
<p>邮箱地址：<input type="text" name="eamil"/></p>
<input type="button" value="注册" onclick="send()">
</form>
</body>
</html>
php接收页面
<?php
print_r($_POST);
$name=Array('test111','admin','Admin');
if(isset($_POST)){
if(in_array($_POST['username'],$name)){
echo '用户名已经注册';
}else{
echo '可以注册';
}
}
?>
出现以下错误
解决办法
将XMLHTTPRequest对象设置的头信息
xhr.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
删掉或注释就可以了
