真的坚持添加删除并在我的管理页面上的用户表中添加行

Question

AdminAccount.php

<?php

ob_start();
include 'connection.php';
$ses = $_SESSION['user_id'];

$username = $_POST['username'];
$password = $_POST['password'];
$email = $_POST['email'];

echo "<h3> User Account Information </h3>";

if (isset($_SESSION["user_id"] )) {

    print "<table border=1 cellpadding='5' width = 100px height = 100px align='middle'>";

    print "<th>username</ th>";

    print "<th>Password</ th>";

    print "<th>email</ th>";

    print "<th>edit information</ th>";

    print "<th>delete information</ th>";

    $query = "SELECT * FROM Register";


    $result = mysqli_query($connection, $query);

    while ($row = mysqli_fetch_array($result)) {
        echo " <tr>";

        echo "<td>" . $row['username'] . "</td>";

        echo "<td>" . $row['password'] . "</td>";

        echo "<td>" . $row['email'] . "</td>";

        echo " <form action= InfoActions.php  method= 'post'>
        <td><input type= 'submit' name = 'type' value= 'Edit'/></td>
        <td><input type= 'submit' name = 'type' value= 'Delete'/></td>";

        echo "</tr>";
//echo "<td><a href='EditInfo.php?id=" . $row['user_id'] . "'>Edit</a></td>";

    }
    echo "</table>";
    }


    if(isset($_POST['submit'])){

        $query = ("UPDATE Register SET username = '$username' , password = '$password' , email = '$email' WHERE user_id='$ses'");


$result = mysqli_query($connection,$query);


header('location:ProtectedPage.php');   
//Temporarily echo $query for debugging purposes    

//run $query
}               

InfoActions.php

<?php

    session_start();
    include 'connection.php';
    $ses = $_SESSION['user_id'];
    if (isset($_POST['type'])) {
        $urls = array(
            'Edit Information' => 'EditInfo.php',
            'Delete' => 'DeleteInfo.php'
        );
        $url = $urls[$_POST['type']];
    }

    ?>

I'll let you know now I copied the InfoActions.php code and changed it a bit but don't fully understand the (isset($_POST['type']), $url and $url = $urls[$_POST['type']]; bit!

EditInfo.php

    <form method="post" action="AdminAccount.php">
            <lable for ="Username" > Username: </lable> </br>
            <input type="text" name="username" value=''/> </br>

            <lable for ="Password" > Password: </lable> </br>
            <input type="password" name="password" /> </br>

            <lable for ="Email" > Email: </lable> </br>
            <input type="email" name="email" /> </br>

            <input type="submit" name="submit" value="submit" />
            <input type="reset"  value="clear" />
        </form>

DeleteInfo.php

    <?php
    session_start();
    $ses = $_SESSION['user_id'];
    $query = "DELETE FROM Register WHERE user_id=$user_id'";
    $result = mysql_query($query);
    ?>