如何添加一个按钮到我的PHP表单，删除行从我的MYSQL数据库 - How to add a button to my PHP form that deletes rows from my MYSQL database

我是php编程新手。

我正在添加每一行删除按钮，但它不应该工作。

这是我的html代码:

<!DOCTYPE html>
<html>
<head>
</head>
<body>
<?php
    $connection = mysql_connect('localhost', 'root','');
if (!$connection)
{
    die("Database Connection Failed" . mysql_error());
}
$select_db = mysql_select_db( "emp",$connection);
if (!$select_db)
{
    die("Database Selection Failed" . mysql_error());
}
    $sql = "SELECT * FROM venu ";     
    $result = mysql_query($sql) or die(mysql_error());
    ?>
    <table border="2" style= " margin: 0 auto;" id="myTable">
      <thead>
        <tr>
          <th>name</th>
          <th>id</th>
          <th>rollnumber</th>
          <th>address</th>
          <th>phonenumber</th>
        </tr>
      </thead>
      <tbody>
      <?php
            while($row = mysql_fetch_array($result))
            {
              echo "<tr>";
                echo "<td>" . $row['name'] . "</td>";
                echo "<td>" . $row['id'] . "</td>";
                echo "<td>" . $row['rollnumber'] . "</td>";
                echo "<td>" . $row['address'] . "</td>";
                echo "<td>" . $row['phonenumber'] . "</td>";
               echo "<td><form action='delete.php' method='POST'><input type='hidden'  value='".$row["address"]."'/><input type='submit' name='submit-btn' value='delete' /></form></td></tr>";
                echo "</tr>";
                
            }
            ?>
            </tbody>
            </table>
    </body>
    </html>

我的删除代码:

<?php
$connection = mysql_connect('localhost', 'root','');
if (!$connection)
{
    die("Database Connection Failed" . mysql_error());
}
$select_db = mysql_select_db( "emp",$connection);
if (!$select_db)
{
    die("Database Selection Failed" . mysql_error());
}
    error_reporting(0);
    session_start();
    $name = $_POST['name'];
    $id = $_POST['id'];
    $rollnumber = $_POST['rollnumber'];
    $address = $_POST['address'];
    $phonenumber = $_POST['phonenumber'];
    if($name!='' and $id!='')
    {
        $sql = mysql_query("DELETE FROM 'venu' WHERE name='balaji'AND id='93'AND rollnumber='93'AND address='bangalore'AND phonenumber='1234567890'");
    echo "<br/><br/><span>deleted successfully...!!</span>";
}
else{
echo "<p>ERROR</p>";
}
mysql_close($connection); 
?>

我正在尝试使用按钮删除每一行，但它不工作。

在您的html视图页面中更改echo "<td><a href='delete.php?did=".$row['id']."'>Delete</a></td>";如下:

<?php
while($row = mysql_fetch_array($result))
{
    echo "<tr>";
        echo "<td>" . $row['name'] . "</td>";
        echo "<td>" . $row['id'] . "</td>";
        echo "<td>" . $row['rollnumber'] . "</td>";
        echo "<td>" . $row['address'] . "</td>";
        echo "<td>" . $row['phonenumber'] . "</td>";
        echo "<td><a href='delete.php?did=".$row['id']."'>Delete</a></td>";
    echo "</tr>";
}
?>

PHP delete code:

<?php
if(isset($_GET['did'])) {
    $delete_id = mysql_real_escape_string($_GET['did']);
    $sql = mysql_query("DELETE FROM venu WHERE id = '".$delete_id."'");
    if($sql) {
        echo "<br/><br/><span>deleted successfully...!!</span>";
    } else {
        echo "ERROR";
    }
}
?>

注意:请避免mysql_*，因为mysql_*已从PHP 7。请使用mysqli或PDO。

PDO连接的详细信息http://php.net/manual/en/pdo.connections.php

关于mysqli的更多细节http://php.net/manual/en/mysqli.query.php

首先你需要改变你的按钮，像

echo "<td><a href="delete.php?id='.$row['id'].'">Delete</a></td>";

这将发送您想要删除的行ID到delete.php

其次，你需要改变一点你的delete.php目前是开放的SQL注入。尝试使用mysql或PDO来代替

if(isset($_GET['id'])) {
    $id = $_GET['id'];
    $stmt = $mysqli->prepare("DELETE FROM venu WHERE id = ?");
    $stmt->bind_param('i', $id);
    $stmt->execute(); 
    $stmt->close();
}

当然，如果你需要在delete查询中添加更多参数，你也应该通过按钮传递它们。

编辑:更新记录

的简单示例

你可以把第二个按钮放在桌子上，像

echo "<td><a href="update.php?id='.$row['id'].'">Update</a></td>";

然后，当你点击它，你会有你想要更新的记录的ID。然后在update.php

if(isset($_GET['id'])) {
    $id = $_GET['id'];
    $stmt = $mysqli->prepare("UPDATE venu SET name = ?, rollnumber = ?, address = ? WHERE id = ?");
    $stmt->bind_param('sisi', $name, $rollnumber, $address, $id);
    $stmt->execute(); 
    $stmt->close();
}

在这里(在update.php)你可以有一个表单，你可以用新的数据填充，并传递给变量$name, $rollnumber, $address，然后发布它来更新部分。

PHP MySqli基本用法(select, insert &更新)

修改您的查询以使用用户输入的动态值，现在它是硬编码在那里。

session_start();
require_once 'conn.php';
class myClass extends dbconn {
  public function myClassFunction(){
    try {
      $id = $_GET['id'];
      if(isset($_GET['id'])) {
          $sql = "DELETE FROM tablename WHERE id = ?";
          $stmt = $this->connect()->query($sql);
          $stmt->bind_param('i', $id);
          header("location: ../filepath/index.php");
      }
    } catch (PDOException $e) {
      echo $sql . "<br>" . $e->getMessage();
    }
  }
}

这行是错误的，您需要将WHERE子句设置为从隐藏输入值

获得的数据

$sql = mysql_query("DELETE FROM 'venu' WHERE name='balaji'AND id='93'AND rollnumber='93'AND address='bangalore'AND phonenumber='1234567890'");

应:

$sql = mysql_query("DELETE FROM 'venu' WHERE address='"._POST['address']."'");

在你使用的小格式中，修改:

<input type='hidden'  value='".$row["address"]."'/>

<input type='hidden' name='address' value='".$row["address"]."'/>