PHP工具类 MySQL增删改查工具类_MySQL

MySQL是一种常用的关系型数据库管理系统，可以通过PHP来操作MySQL数据库。下面是一个简单的PHP工具类，包含了MySQL的增删改查操作。

class MySQL {
    private $host;
    private $username;
    private $password;
    private $database;
    private $connection;

    public function __construct($host, $username, $password, $database) {
        $this->host = $host;
        $this->username = $username;
        $this->password = $password;
        $this->database = $database;

        $this->connect();
    }

    private function connect() {
        $this->connection = mysqli_connect($this->host, $this->username, $this->password, $this->database);

        if (!$this->connection) {
            die("连接数据库失败：" . mysqli_connect_error());
        }
    }

    public function query($sql) {
        $result = mysqli_query($this->connection, $sql);

        if (!$result) {
            die("查询失败：" . mysqli_error($this->connection));
        }

        return $result;
    }

    public function insert($table, $data) {
        $columns = implode(", ", array_keys($data));
        $values = "'" . implode("', '", array_values($data)) . "'";
        $sql = "INSERT INTO $table ($columns) VALUES ($values)";

        return $this->query($sql);
    }

    public function update($table, $data, $condition) {
        $set = "";

        foreach ($data as $key => $value) {
            $set .= "$key = '$value', ";
        }

        $set = rtrim($set, ", ");
        $sql = "UPDATE $table SET $set WHERE $condition";

        return $this->query($sql);
    }

    public function delete($table, $condition) {
        $sql = "DELETE FROM $table WHERE $condition";

        return $this->query($sql);
    }

    public function select($table, $condition = "") {
        $sql = "SELECT * FROM $table";

        if (!empty($condition)) {
            $sql .= " WHERE $condition";
        }

        $result = $this->query($sql);
        $data = [];

        while ($row = mysqli_fetch_assoc($result)) {
            $data[] = $row;
        }

        return $data;
    }

    public function close() {
        mysqli_close($this->connection);
    }
}

使用示例：

$host = "localhost";
$username = "root";
$password = "password";
$database = "mydatabase";

$mysql = new MySQL($host, $username, $password, $database);

// 插入数据
$data = [
    "name" => "John",
    "age" => 25,
    "email" => "john@example.com"
];
$mysql->insert("users", $data);

// 更新数据
$data = [
    "age" => 26,
    "email" => "john@example.com"
];
$mysql->update("users", $data, "name = 'John'");

// 删除数据
$mysql->delete("users", "name = 'John'");

// 查询数据
$users = $mysql->select("users");
print_r($users);

$mysql->close();

请注意，这只是一个简单的示例，实际使用中可能需要根据具体需求进行修改和扩展。