PHP PDO 数据库操作类

<?php
/**
 * PDO-MySQL数据库操作类 单例模式
 * @author Luocz
 * @license https://runoops.com/
 * @version v1.0.0
 */
class MyPDO
{
    protected static $_instance = null;
    protected $dsn;
    protected $dbh;
    protected $debug = false;

    /**
     * 构造方法
     * @param Array $config
     * @return MyPDO
     */
    private function __construct($config = [])
    {
        try {
           
            $type = isset($config['type']) ? $config['type'] : 'mysql';
            $host = isset($config['host']) ? $config['host'] : '127.0.0.1';
            $port = isset($config['port']) ? $config['port'] : '3306';
            $user = isset($config['user']) ? $config['user'] : 'root';
            $pwd = isset($config['pwd']) ? $config['pwd'] : 'root';
            $dbname = isset($config['dbname']) ? $config['dbname'] : 'runoops-test';
            $charset = isset($config['charset']) ? $config['charset'] : 'utf8';
        
            $this->dsn = "{$type}:host={$host};port={$port};dbname={$dbname};charset={$charset}";
            $this->dbh = new PDO($this->dsn, $user, $pwd);
            // $this->dbh->exec('SET character_set_connection=' . $charset . ', character_set_results=' . $charset . ', character_set_client=binary');
        } catch (PDOException $e) {
            $this->outputError($e->getMessage());
        }
    }

    /**
     * 防止克隆
     * 
     */
    private function __clone()
    {
    }

    /**
     * 单例实例
     * 
     * @return Object
     */
    public static function getInstance($config)
    {
        if (self::$_instance === null) {
            self::$_instance = new self($config);
        }
        return self::$_instance;
    }

    /**
     * 执行SQL
     * @param $sql string 执行的SQL语句
     * @return object PDOStatement
     */
    public function query($sql)
    {
        $stmt = $this->dbh->query($sql);
        if ($stmt === false) {
            $error = $this->dbh->errorInfo();
            $this->outputError("Query ERROR : {$error[1]}({$error[0]}): {$error[2]}");
        }
        return $stmt;
    }

    /**
     * Query 查询所有数据
     *
     * @param String $strSql SQL语句
     * @return Array
     */
    public function fetchAll($strSql)
    {
        $stmt = $this->query($strSql);
        if ($stmt) {
            $stmt->setFetchMode(PDO::FETCH_ASSOC);
            $result = $stmt->fetchAll();
        } else {
            $result = null;
        }
        return $result;
    }

    /**
     * 查询一条数据
     *
     * @param String $strSql SQL语句
     * @return Array
     */
    public function fetchRow($strSql)
    {
        $stmt = $this->query($strSql);
        if ($stmt) {
            $stmt->setFetchMode(PDO::FETCH_ASSOC);
            $result = $stmt->fetch();
        } else {
            $result = null;
        }
        return $result;
    }

    /**
     * 更新
     *
     * @param String $table 表名
     * @param Array $arrayDataValue 字段与值
     * @param String $where 条件
     * @return Int
     */
    public function update($table, $arrayDataValue, $where = '')
    {
        $this->checkFields($table, $arrayDataValue);
        if ($where) {
            $strSql = '';
            foreach ($arrayDataValue as $key => $value) {
                $strSql .= ", `$key`='$value'";
            }
            $strSql = substr($strSql, 1);
            $strSql = "UPDATE `$table` SET $strSql WHERE $where";
        } else {
            $strSql = "REPLACE INTO `$table` (`" . implode('`,`', array_keys($arrayDataValue)) . "`) VALUES ('" . implode("','", $arrayDataValue) . "')";
        }
        $result = $this->dbh->exec($strSql);
        return $result;
    }

    /**
     * Insert 插入
     *
     * @param String $table 表名
     * @param Array $arrayDataValue 字段与值
     * @return Int
     */
    public function insert($table, $arrayDataValue)
    {
        $this->checkFields($table, $arrayDataValue);
        $strSql = "INSERT INTO `$table` (`" . implode('`,`', array_keys($arrayDataValue)) . "`) VALUES ('" . implode("','", $arrayDataValue) . "')";
        $num = $this->dbh->exec($strSql);
        if($num > 0){
            return $this->dbh->lastInsertId();
        }else{
            return $num;
        }
        
    }

    /**
     * Replace 覆盖方式插入
     *
     * @param String $table 表名
     * @param Array $arrayDataValue 字段与值
     * @return Int
     */
    public function replace($table, $arrayDataValue)
    {
        $this->checkFields($table, $arrayDataValue);
        $strSql = "REPLACE INTO `$table`(`" . implode('`,`', array_keys($arrayDataValue)) . "`) VALUES ('" . implode("','", $arrayDataValue) . "')";
        $result = $this->dbh->exec($strSql);
        return $result;
    }

    /**
     * 删除
     *
     * @param String $table 表名
     * @param String $where 条件
     * @return Int
     */
    public function delete($table, $where = '')
    {
        if ($where == '') {
            $this->outputError("'WHERE' is Null");
        } else {
            $strSql = "DELETE FROM `$table` WHERE $where";
            $result = $this->dbh->exec($strSql);
            return $result;
        }
    }

    /**
     * execSql 执行SQL语句
     *
     * @param String $strSql
     * @return Int
     */
    public function execSql($strSql)
    {
        $result = $this->dbh->exec($strSql);
        return $result;
    }

    /**
     * 获取指定列的数量
     * 
     * @param string $table
     * @param string $field_name
     * @param string $where
     * @return int
     */
    public function getCount($table, $field_name, $where = '')
    {
        $strSql = "SELECT COUNT($field_name) AS NUM FROM $table";
        if ($where != '') $strSql .= " WHERE $where";
        $arrTemp = $this->fetchRow($strSql);
        return $arrTemp['NUM'];
    }

    /**
     * 获取表引擎
     * 
     * @param String $dbName 库名
     * @param String $tableName 表名
     * @return String
     */
    public function getTableEngine($dbName, $tableName)
    {
        $strSql = "SHOW TABLE STATUS FROM $dbName WHERE Name='" . $tableName . "'";
        $arrayTableInfo = $this->fetchAll($strSql);
        return $arrayTableInfo[0]['Engine'];
    }

    /**
     * beginTransaction 事务开始
     */
    private function beginTransaction()
    {
        $this->dbh->beginTransaction();
    }

    /**
     * commit 事务提交
     */
    private function commit()
    {
        $this->dbh->commit();
    }

    /**
     * rollback 事务回滚
     */
    private function rollback()
    {
        $this->dbh->rollback();
    }

    /**
     * transaction 通过事务处理多条SQL语句
     * 调用前需通过getTableEngine判断表引擎是否支持事务
     *
     * @param array $arraySql
     * @return Boolean
     */
    public function execTransaction($arraySql)
    {
        $retval = 1;
        $this->beginTransaction();
        foreach ($arraySql as $strSql) {
            if ($this->execSql($strSql) == 0) $retval = 0;
        }
        if ($retval == 0) {
            $this->rollback();
            return false;
        } else {
            $this->commit();
            return true;
        }
    }

    /**
     * 设置debug
     */
    public function setDebug($flag = false)
    {
        $this->debug = $flag;
    }

    /**
     * checkFields 检查指定字段是否在指定数据表中存在
     *
     * @param String $table
     * @param array $arrayField
     */
    private function checkFields($table, $arrayFields)
    {
        $fields = $this->getFields($table);
        foreach ($arrayFields as $key => $value) {
            if (!in_array($key, $fields)) {
                $this->outputError("Unknown column `$key` in field list.");
            }
        }
    }

    /**
     * getFields 获取指定数据表中的全部字段名
     *
     * @param String $table 表名
     * @return array
     */
    private function getFields($table)
    {
        $fields = array();
        $stmt = $this->query("SHOW COLUMNS FROM $table");
        $stmt->setFetchMode(PDO::FETCH_ASSOC);
        $result = $stmt->fetchAll();
        foreach ($result as $rows) {
            $fields[] = $rows['Field'];
        }
        return $fields;
    }

    /**
     * 输出错误信息
     * 
     * @param String $strErrMsg
     */
    private function outputError($strErrMsg)
    {
        throw new Exception('MySQL Error: ' . $strErrMsg);
    }

    /**
     * destruct 关闭数据库连接
     */
    public function destruct()
    {
        $this->dbh = null;
    }
}

<?php
// 引入操作类
include 'MyPDO.php';
    
//测试
$dbconfig = [
    'type' => 'mysql',
    'host' => 'localhost',
    'port' => 3306,
    'dbname' => 'runoops-test',
    'user' => 'root',
    'pwd' => 'root',
    'charset' => 'utf8',
];
//获取pdo单例实例
$mypdo= MyPDO::getInstance($dbconfig);


// 添加数据
// $insertId = $mypdo->insert('websites', ['name' => 'testDB2','url' => 'test2.xxx.com','alexa' => 100,'country' => 'CN']);
// echo 'insert id = ' . $insertId;
// echo '<br />';

// 更新数据,返回影响条数
// $numUp = $mypdo->update('websites', ['url' => 'test2.xxx2.com'],'name = "testDB2"');
// var_dump($numUp);

//获取websites 前10条
$list=$mypdo->fetchAll('select * from websites limit 10');
var_dump($list);


// $list=$mypdo->fetchRow('select * from websites where id = 1');
// var_dump($list);


//删除id=14的数据
// $mypdo->delete('websites','id=14');

?>