PHP development student management tutorial database operation

Create action.php file

This file uses switch and case statements to process data such as deletion, modification, and addition. On the same page, reducing the duplication of code

##The code is as follows

<?php
header("content-type:text/html;charset=utf8");
$conn=mysqli_connect("localhost","root","root","study");
mysqli_set_charset($conn,"utf8");
if($conn){
    switch ($_GET['action']){
        case 'add'://add
            $name = $_POST['name'];
            $sex = $_POST['sex'];
            $age = $_POST['age'];
            $class = $_POST['class'];
            $sql = "insert into stu (`name`, sex, age, class) values ('$name', '$sex','$age','$class')";
            $rw = mysqli_query($conn,$sql);
            if ($rw > 0){
                echo "<script>alert('添加成功');</script>";
            }else{
                echo "<script>alert('添加失败');</script>";
            }
            header('Location: index.php');
            break;
        case 'del'://get
            $id = $_GET['id'];
            $sql = "delete from stu where id='$id'";
            $rw = mysqli_query($conn,$sql);
            if ($rw > 0){
                echo "<script>alert('删除成功');</script>";
            }else{
                echo "<script>alert('删除失败');</script>";
            }
            header('Location: index.php');
            break;
        case 'edit'://post
            $id = $_POST['id'];
            $name = $_POST['name'];
            $age = $_POST['age'];
            $class = $_POST['class'];
            $sex = $_POST['sex'];
//    echo $id, $age, $age, $name;
            $sql = "update stu set name='$name', age='$age',sex='$sex',class='$class' where id='$id';";
//    $sql = "update myapp.stu set name='jike',sex='女', age=24,classid=44 where id=17";
//            print $sql;
            $rw = mysqli_query($conn,$sql);
//            var_dump($rw);
//            die();
            if ($rw > 0){
                echo "<script>alert('更新成功');</script>";
            }else{
                echo "<script>alert('更新失败');</script>";
            }
            header('Location: index.php');
            break;
        default:
            header('Location: index.php');
            break;
    }
}else{
    die('数据库连接失败' .mysqli_connect_error());
}
?>