mysql异常过程捕捉

-- 示例代码
try {
    $conn = new mysqli($servername, $username, $password, $dbname);
    if ($conn->connect_error) {
        die("连接失败: " . $conn->connect_error);
    }
    
    $sql = "SELECT * FORM users";  // 拼写错误，应为FROM
    $result = $conn->query($sql);
    
    if ($result) {
        // 处理查询结果
    } else {
        echo "查询失败: " . $conn->error;
    }
    
    $conn->close();
} catch (Exception $e) {
    echo "发生异常: " . $e->getMessage();
}

-- 示例代码
try {
    $conn = new mysqli($servername, $username, $password, $dbname);
    if ($conn->connect_error) {
        die("连接失败: " . $conn->connect_error);
    }
    
    $sql = "INSERT INTO users (username, email) VALUES ('testuser', 'test@example.com')";
    if ($conn->query($sql) === TRUE) {
        echo "新记录插入成功";
    } else {
        echo "插入失败: " . $conn->error;
    }
    
    $conn->close();
} catch (Exception $e) {
    echo "发生异常: " . $e->getMessage();
}

-- 示例代码
try {
    $conn = new mysqli($servername, $username, $password, $dbname);
    if ($conn->connect_error) {
        die("连接失败: " . $conn->connect_error);
    }
    
    // 执行数据库操作
    
    $conn->close();
} catch (Exception $e) {
    echo "发生异常: " . $e->getMessage();
}