diff --git "a/\345\276\220\350\257\227\346\201\222/20220525-cooike\344\270\216session.md" "b/\345\276\220\350\257\227\346\201\222/20220525-cooike\344\270\216session.md"
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index 0000000000000000000000000000000000000000..a22c3adac7a28d2cf6ce40352b846317af628606
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+```html
+        <!--login.html-->
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <title>学生管理系统登陆界面</title>
+</head>
+<body>
+<h1 align="center">学生信息系统登陆界面</h1>
+    <form action="login.php" method="post">
+        <table align="center">
+            <tr>
+                <td>用户名:</td>
+                <td><input type="text" name="username" id=""></td>
+                </tr>
+            <tr>
+                <td>密码:</td>
+                <td><input type="password" name="password" id=""></td>
+            </tr>
+            <tr><td></td>  <td><input type="submit" value="提交"></td></tr>
+        </table>
+        
+    </form>
+</body>
+</html>
+```
+
+```php
+//index.php
+<html>
+<head>
+    <script>
+        function zhuxiao(){
+            if(!window.confirm("确定要注销吗？")){
+                return false;
+            }
+        }
+    </script>
+</head>
+<body>
+<div align="center">
+    <?php
+    include_once('conn.php');
+    $sql = "select * from `user` order by id";
+    $result = mysqli_query($con,$sql);
+    session_start();
+    $user = $_SESSION['username'];
+    if (isset($user) && $user=="admin") {
+        echo "学生管理系统欢迎您：". $user;
+        echo "<a href='loginout.php'onclick=\"return zhuxiao();\">注销</a>";
+
+    }else{
+        header('location:login.php');
+    }
+    ?>
+</div>
+</body>
+</html>
+
+
+<html>
+<head>
+    <meta charset="utf-8">
+    <title>学生管理系统</title>
+    <script>
+        function del(){
+            if(!window.confirm("确定要删除吗？")){
+                return false;
+            }
+        }
+    </script>
+</head>
+<body>
+<div align="center">
+<h1 align="center">学生管理系统——首页</h1>
+<table border="1" width="450" align="center">
+    <tr>
+        <th>学号</th>
+        <th>姓名</th>
+        <th>分数</th>
+        <th>编辑</th>
+    </tr>
+    <?php
+    if(!mysqli_num_rows($result)) {
+        echo "<tr align='center'><td colspan='4'>暂无数据</td></tr>";
+    }else {
+        while ($row = mysqli_fetch_assoc($result)) {
+            ?>
+            <tr align="center">
+                <td><?php echo $row['id'] ?></td>
+                <td><?php echo $row['name'] ?></td>
+                <td><?php echo $row['score'] ?></td>
+                <td><a href="edit.php?id=<?php echo $row['id'] ?>">修改</a>|
+                    <a href="delete.php?id=<?php echo $row['id'] ?>" onclick="return del();">删除</a></td>
+            </tr>
+            <?php
+        }
+    }
+    ?>
+</table>
+<a href="add.php">添加学生信息</a>
+</div>
+</body>
+</html>
+
+
+//login.php
+<?php
+
+session_start();
+$username="admin";
+$password="123456";
+if ($_POST['username']==$username && $_POST['password']==$password){
+    echo "登陆成功";
+    $_SESSION['username']=$username;
+    header('location:index.php');
+}else{
+    die("登陆失败") ;
+}
+
+//conn.php
+<?php
+/**
+ * Created by PhpStorm.
+ * User: Administrator
+ * Date: 2022/5/24
+ * Time: 16:37
+ */
+error_reporting(E_ALL ^ E_WARNING);
+
+$con =mysqli_connect('127.0.0.1','root','123456','student') or die("服务器连接失败！");
+
+mysqli_query($con,'set names utf8');
+
+//loginout.php
+<?php
+/**
+ * Created by PhpStorm.
+ * User: Administrator
+ * Date: 2022/5/25
+ * Time: 10:44
+ */
+session_start();
+unset($_SESSION['username']);
+echo "注销成功";
+
+//add.php
+<?php
+/**
+ * Created by PhpStorm.
+ * User: Administrator
+ * Date: 2022/5/24
+ * Time: 16:41
+ */
+?>
+<html>
+<head>
+    <title>添加学生信息</title>
+</head>
+<body>
+<div align="center">
+<h1>添加学生信息</h1>
+<form action="save.php" method="post">
+    <table border="1" width="300">
+        <tr>
+            <th>姓名</th>
+            <td><input type="text" name="name" ></td>
+        </tr>
+        <tr>
+            <th>分数</th>
+            <td><input type="text" name="score" ></td>
+        </tr>
+        <tr>
+            <td colspan="2" align="center"><input type="submit" value="提交" name="submit">
+                &nbsp;&nbsp;&nbsp;&nbsp; <input type="reset" name="reset" value="取消"></td>
+        </tr>
+    </table>
+    <a href="index.php">返回</a>
+</form>
+</div>
+</body>
+</html>
+
+                    //save.php
+                    <?php
+include_once('conn.php');
+if (!isset($_POST['submit'])){
+    die("非法访问！") ;
+}
+
+$name=$_POST['name'];
+$score=$_POST['score'];
+
+$sql = "insert into `user` (name,score) values ('$name','$score')";
+
+$ret = mysqli_query($con,$sql);
+
+if ($ret){
+    echo "添加成功";
+    header('location:index.php');
+}else{
+    echo "添加失败 <a href = './index.php'>返回首页</a>";
+}
+
+//delete.php
+<?php
+include_once ('conn.php');
+$id=$_GET['id'];
+$sql="delete from `user` where id=$id";
+$result= mysqli_query($con,$sql);
+if ($result){
+    echo "删除成功";
+    header('location:index.php');
+}else{
+    echo "删除失败";
+    header('location:index.php');
+
+}
+
+//edit.php
+<?php
+include_once ("conn.php");
+if(!isset($_GET['id'])){
+    die("非法访问");
+}
+$id=$_GET['id'];
+
+$sql = "select * from `user` where id=$id";
+$result = mysqli_query($con,$sql);
+$row = mysqli_fetch_assoc($result);
+?>
+<html>
+<head>
+    <title>修改学生信息</title>
+</head>
+<body>
+<div align="center">
+<h1>修改学生信息</h1>
+<form action="update.php" method="post">
+    <table border="1" width="300">
+        <tr>
+            <th>姓名</th>
+            <td><input type="text" name="name" ></td>
+        </tr>
+        <tr>
+            <th>分数</th>
+            <td><input type="text" name="score" ></td>
+        </tr>
+        <input type="text" name="id" value="<?php echo $row['id'] ?>" hidden>
+
+        <tr>
+            <td colspan="2" align="center"><input type="submit" value="提交" name="submit">
+                &nbsp;&nbsp;&nbsp;&nbsp; <input type="reset" name="reset" value="取消"></td>
+        </tr>
+    </table>
+    <a href="index.php">返回</a>
+</form>
+</div>
+</body>
+</html>
+                    //update.php
+                    <?php
+include_once ('conn.php');
+if(!isset($_POST['submit'])){
+    die("非法访问！");
+}
+$id=$_POST['id'];
+$name=$_POST['name'];
+$score=$_POST['score'];
+$sql="update `user` set name='$name', score='$score' where id=$id";
+$result = mysqli_query($con,$sql);
+if ($result)  {
+    echo "修改成功";
+    header('location:index.php');
+}else{
+    echo "修改失败 <a href='./index.php'>返回首页</a>";
+}
+
+```
+
+```mysql
+create database Student charset utf8;
+use Student;
+create table user(
+id int primary key auto_increment,
+name varchar(100) not null,
+score decimal(4,1) not null
+);
+```
+
