php连接mysql使用 pdo增删改查的实例

下面是一个使用PHP PDO连接MySQL数据库进行增删改查的实例：

1. 连接到MySQL数据库：

   
   <?php
   $host = 'localhost';
   $dbname = 'your_database_name';
   $username = 'your_username';
   $password = 'your_password';

try { $conn = new PDO("mysql:host=$host;dbname=$dbname;charset=utf8", $username, $password); $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); echo "成功连接到数据库"; } catch(PDOException $e) { echo "连接数据库失败：" . $e->getMessage(); } ?>

2. 插入数据：
```php
<?php
// 假设数据为：
$name = "John";
$age = 25;
$email = "john@example.com";

$sql = "INSERT INTO your_table_name (name, age, email) VALUES (?, ?, ?)";

try {
    $stmt = $conn->prepare($sql);
    $stmt->execute([$name, $age, $email]);

    echo "插入数据成功";
} catch(PDOException $e) {
    echo "插入数据失败：" . $e->getMessage();
}
?>

3. 更新数据：

   
   <?php
   // 假设要更新的数据为：
   $id = 1;
   $newEmail = "new_email@example.com";

$sql = "UPDATE your_table_name SET email = ? WHERE id = ?";

try { $stmt = $conn->prepare($sql); $stmt->execute([$newEmail, $id]);

echo "更新数据成功";

} catch(PDOException $e) { echo "更新数据失败：" . $e->getMessage(); } ?>

4. 删除数据：
```php
<?php
// 假设要删除的数据id为：
$id = 1;

$sql = "DELETE FROM your_table_name WHERE id = ?";

try {
    $stmt = $conn->prepare($sql);
    $stmt->execute([$id]);

    echo "删除数据成功";
} catch(PDOException $e) {
    echo "删除数据失败：" . $e->getMessage();
}
?>

5. 查询数据：

   
   <?php
   // 假设要查询的数据条件为：
   $name = "John";

$sql = "SELECT * FROM your_table_name WHERE name = ?";

try { $stmt = $conn->prepare($sql); $stmt->execute([$name]);

$result = $stmt->fetchAll(PDO::FETCH_ASSOC);

foreach ($result as $row) {
    echo "ID: " . $row['id'] . "<br>";
    echo "Name: " . $row[' echo "Age: " . $row['age'] . "<br>";
    echo "Email: " . $row['email'] . "<br>";
    echo "<br>";
}

} catch(PDOException $e) { echo "查询数据失败：" . $e->getMessage(); } ?>

请确保将上述示例代码中的"your_database_name"替换为你实际的数据库名称，"your_username"和"your_password"替换为你的数据库用户名和密码，"your_table_name"替换为你的表名。