js封装ajx

来源：互联网发布：光伏产业数据查询编辑：程序博客网时间：2024/06/06 20:23

<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>ajax登录</title>
</head>

<body>
<div>
<div id="showInfo"></div>
<form id="form">
用户名：<input type="text" name="username" id="username"><br>
密码：<input type="password" name="password" id="password">
<input type="button" id="btn" value="登录">
</form>

</div>
<script type="text/javascript">
window.onload = function(){
var btn = document.getElementById('btn');
btn.onclick = function(){
var username = document.getElementById('username').value;
var password = document.getElementById('password').value;

//第一步：创建对象
//秘书出场
var xhr = null;
if(window.XMLHttpRequest){
xhr = new XMLHttpRequest();
}else{
xhr = new ActiveXObject("Microsoft.XMLHTTP");
}
//初始化
//准备好了
var url = './check.php?username='+username+"&password="+password;
xhr.open('post',url,false);

//这段代码在xhr.send();执行完之后才能执行
//这件事做完了怎么办
//事情办完之后干什么
xhr.onreadystatechange = function(){
if(xhr.readyState == 4){
if(xhr.status == 200){
alert(1);
var data = xhr.responseText;
if(data == 1){
document.getElementById('showInfo').innerHTML = '用户名或者密码错误';
}else if(data == 2){
document.getElementById('showInfo').innerHTML = '登录成功';
}
}
};
}

//实际的去做这件事
//去做这件事情
xhr.send(null);

alert(2);

}

}

</script>
</body>
</html>

阅读全文

0 0