用 PHP & MySQL 删除一行

Question

我是 php 和 SQL 的新手，我只是在玩一个项目，以了解如何访问、更新和删除数据库中的数据。

我已经设法显示了选定的数据，创建了一个按钮来删除特定的 ID，但确实需要一些帮助来删除选定的行或记录，而不是在我的删除 php 脚本中对 ID 进行硬编码。

这是我的脚本示例：

<?php

    $sql = "SELECT id, firstname, lastname, joinDate FROM customers";
    $result = $conn->query($sql);

    if ($result->num_rows > 0) {
        // output data of each row

        while($row =  $result->fetch_assoc()) {
            echo 
                "<div class='trow'>" . 
                $row["id"]. ": " . 
                $row["firstname"] . " " . 
                $row["lastname"]. " " . 
                $row["joinDate"]. " " . 
                "<span class='deleteMember'>
                    <form action='deleteMember.php' method='POST'>
                        <button type='submit'>Delete</button>
                    </form>
                </span>" . " " . 
                "<span class='editMember'><a href='#'>Edit</a></span>" . 
                "<br></div>";
        }

    } else {
        echo "0 results";
    }

    $conn->close();

?>

这里是delete.php

<?php

    // sql to delete a record
    $sql = "DELETE FROM customers WHERE id='6' ";

    if ($conn->query($sql) === TRUE) {
       header("Location: index.php");
    } else {
        echo "Error deleting record: " . $conn->error;
    }

    $conn->close();

?>

我希望它做的是，删除您从中点击删除按钮的行，而不仅仅是删除我在 delete.php 脚本中指定的行。我通过发布 id 了解它应该如何工作，但不知道该怎么做。

Answer 1

这样做

<?php

    // sql to delete a record
    $sql = "DELETE FROM customers WHERE id='".$_GET['id']."' ";

    if ($conn->query($sql) === TRUE) {
       header("Location: index.php");
    } else {
        echo "Error deleting record: " . $conn->error;
    }

    $conn->close();

?>

<?php

    $sql = "SELECT id, firstname, lastname, joinDate FROM customers";
    $result = $conn->query($sql);

    if ($result->num_rows > 0) {
        // output data of each row

        while($row =  $result->fetch_assoc()) {
            echo 
                "<div class='trow'>" . 
                $row["id"]. ": " . 
                $row["firstname"] . " " . 
                $row["lastname"]. " " . 
                $row["joinDate"]. " " . 
                "<span><a href='deleteMember.php?id=".$row['id']."'>Delete</a></span>" . 
                "<span class='editMember'><a href='#'>Edit</a></span>" . 
                "<br></div>";
        }

    } else {
        echo "0 results";
    }

    $conn->close();
?>

Answer 2

用这个代替你的表格

<a href="deleteMember.php?id=<?php echo $row['id'];?>">DELETE</a>

并且在您的删除查询中必须如下所示

$sql = "DELETE FROM customers WHERE id='".$_GET['id']."' ";

Answer 3

或留在您的帖子表单中：

 while($row =  $result->fetch_assoc()) {
            echo 
                "<div class='trow'>" . 
                $row["id"]. ": " . 
                $row["firstname"] . " " . 
                $row["lastname"]. " " . 
                $row["joinDate"]. " " . 
                "<span class='deleteMember'>
                    <form action='deleteMember.php' method='POST'>
                        <input type='hidden' name='myid' value='".$row['id']."' />
                        <button type='submit'>Delete</button>
                    </form>
                </span>" . " " . 
                "<span class='editMember'><a href='#'>Edit</a></span>" . 
                "<br></div>";
        }

在你的 delete.php 中：

<?php
    $id=(int) $_POST['myid'];

    // sql to delete a record
    $sql = "DELETE FROM customers WHERE id=".$id;

    if ($conn->query($sql) === TRUE) {
       header("Location: index.php");
    } else {
        echo "Error deleting record: " . $conn->error;
    }

    $conn->close();

?>

Answer 4

无需为删除或编辑目的添加额外的form 元素。尝试这种方式传递id的行进行Eelete或Edit操作

while($row =  $result->fetch_assoc()) 
       {
            $id=$row['id'];// capture your row id & pass to your delete & edit
            echo 
             "<div class='trow'>" . 
                 $row["id"]. ": " . 
                 $row["firstname"] . " " . 
                 $row["lastname"]. " " . 
                 $row["joinDate"]. " " . 
                 "<span class='deleteMember'>
                    <a href='deleteMember.php?id=<?=$id;?>'>Delete</a>
                 </span>" . " " . 
                 "<span class='editMember'>
                     <a href='editMember.php?id=<?=$id;?>'>Edit</a>
                 </span>" . 
                 "<br>
           </div>";
        }

编辑： 然后在您的相关页面上捕捉id为您的操作。

//deleteMember.php

<?php
    $id=$_GET['id'];
    // sql to delete a record
    $sql = "DELETE FROM customers WHERE id='".$id."'";

    if ($conn->query($sql) === TRUE) {
       header("Location: index.php");
    } else {
        echo "Error deleting record: " . $conn->error;
    }

    $conn->close();

?>

注意：请改用PDO或MYSQLi的Prepared Statements，以避免SQL Injection和手动转义。