Javascript 缓存信息并将其保留到页面刷新
我有一个html页面，可以从用户那里获取登录用户名和密码，并使用PHP从数据库中获取信息。我正在使用javascript将变量username和password传递给PHP，因为我不想显示后台进程。代码如下： 用于HTMLJavascript 缓存信息并将其保留到页面刷新,javascript,php,jquery,html,Javascript,Php,Jquery,Html,我有一个html页面，可以从用户那里获取登录用户名和密码，并使用PHP从数据库中获取信息。我正在使用javascript将变量username和password传递给PHP，因为我不想显示后台进程。代码如下： 用于HTML <script> function PostData() { // 1. Create XHR instance - Start var xhr; if (window.XMLHttpRequest) { xhr = new XMLHttpRequ
<script>
function PostData() {
// 1. Create XHR instance - Start
var xhr;
if (window.XMLHttpRequest) {
xhr = new XMLHttpRequest();
}
else if (window.ActiveXObject) {
xhr = new ActiveXObject("Msxml2.XMLHTTP");
}
else {
throw new Error("Ajax is not supported by this browser");
}
// 1. Create XHR instance - End
// 2. Define what to do when XHR feed you the response from the server - Start
xhr.onreadystatechange = function () {
if (xhr.readyState === 4) {
if (xhr.status == 200 && xhr.status < 300) {
document.getElementById('div1').innerHTML = xhr.responseText;
}
}
}
// 2. Define what to do when XHR feed you the response from the server - Start
var userid = document.getElementById("userid").value;
var pid = document.getElementById("pid").value;
// var image = document.getElementById("image").value;
// 3. Specify your action, location and Send to the server - Start
xhr.open('POST', 'login.php');
//xhr.open('POST', 'config.php');
xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
xhr.send("userid=" + userid + "&pid=" + pid);
//xhr.send("&pid=" + pid);
// 3. Specify your action, location and Send to the server - End
}
</script>
</head>
<body>
<form>
<label for="userid">User ID :</label><br/>
<input type="text" name ="userid" id="userid" /><br/>
<label for="pid">Password :</label><br/>
<input type="password" name="password" id="pid" /><br><br/>
<div id="div1">
<input type="button" value ="Login" onClick="PostData()" />
</div>
</form>
函数PostData（）{
//1.创建XHR实例-启动
var-xhr；
if（window.XMLHttpRequest）{
xhr=newXMLHttpRequest（）；
}
else if（window.ActiveXObject）{
xhr=新的ActiveXObject（“Msxml2.XMLHTTP”）；
}
否则{
抛出新错误（“此浏览器不支持Ajax”）；
}
//1.创建XHR实例-结束
//2.定义当XHR从服务器向您提供响应时要做什么-启动
xhr.onreadystatechange=函数（）{
if（xhr.readyState==4）{
如果（xhr.status==200&&xhr.status<300）{
document.getElementById（'div1'）。innerHTML=xhr.responseText；
}
}
}
//2.定义当XHR从服务器向您提供响应时要做什么-启动
var userid=document.getElementById（“userid”）.value；
var pid=document.getElementById（“pid”）.value；
//var image=document.getElementById（“image”）.value；
//3.指定您的操作、位置并发送到服务器-启动
open（'POST'，'login.php'）；
//open（'POST'，'config.php'）；
setRequestHeader（“内容类型”，“应用程序/x-www-form-urlencoded”）；
xhr.send（“userid=“+userid+”&pid=“+pid”）；
//xhr.send（“&pid=“+pid”）；
//3.指定您的操作、位置并发送到服务器端
}
用户ID:
密码：
<?php
ini_set('display_errors', 1);
$servername = "localhost";
$username = "root";
$password = "";
$dbname = "dtable";
//session_start();
// Create connection
$conn = mysqli_connect($servername, $username, $password, $dbname);
// Check connection
if (!$conn) {
die("Connection failed: " . mysqli_connect_error());
}
$upload = "E:/Diczon";
$str = '';
$str1 = '';
if(isset($_POST['userid'],$_POST['pid']))
{
$userid = trim($_POST["userid"]);
$pid = trim($_POST["pid"]);
$sql = "SELECT * FROM template WHERE uname = '$userid' and pword = '$pid'";
$result = mysqli_query($conn,$sql);
$row = mysqli_fetch_array($result);
echo "公司".'<br/>';
echo $row['client'].'<br/>'.'<br/>';
echo "第".'<br/>';
echo '<a href="preview.html"/>'.$row['day1'].'</a>'.'<br/>';
?>
<body>
<form enctype="multipart/form-data" id="form" action="login.php" method="POST">
<input type='file' onchange="readURL(this);" name="image" id="image" /><br/><br/>
<img id="blah" src="#" alt="your image" /><br/><br/>
<input type='file' onchange="readURL(this);" name="image1" /><br/><br/>
<input type="submit" value="Upload"/>
</form>
<a href="index.html">BACK</a>//Want to retrieve the output data using this BACK button.
</body>
//要使用此后退按钮检索输出数据。
<?php
//This function starts a session and must be called on your form HTML page, before your submit
session_start();
?>
<?php
//Avoid using * for queries...
$sql = "SELECT * FROM template WHERE uname = '$userid' and pword = '$pid'";
$result = mysqli_query($conn,$sql);
$row = mysqli_fetch_array($result);
//It's missing some validations here, you should consider it...
//The magic is here, you're saving your client in $_SESSION
$_SESSION['client'] = $row['client'];
?>
<?php
print_r($_SESSION);
echo $_SESSION['client'];
?>