封装php连接mysqli类 封装增删改

port = 3306;
        $this->host = '127.0.0.1';
        $this->username = 'name';
        $this->password = 'pwd';
        $this->dbname =  'dbname';
        $this->charset = 'UTF8';
        
        $db = mysqli_connect($this->host, $this->username, $this->password, $this->dbname,$this->port);
        if(!$db){
            $this->error = mysqli_connect_error();
            $this->errno = mysqli_connect_errno();
            return FALSE;
        }
        mysqli_set_charset($db, $this->charset);
        
//        $db = mysqli_init();
//        mysqli_options($db, MYSQLI_OPT_CONNECT_TIMEOUT, 5);  // 5s 超时
//        if(!mysqli_real_connect($db, $this->host, $this->username, $this->password, $this->dbname, $this->port)){
//            $this->error = mysqli_connect_error();
//            $this->errno = mysqli_connect_errno();
//            return FALSE;
//        }
//        mysqli_set_charset($db,$this->charset);
        
        $this->db = $db;
    }
    
    
    /**
     * 数据库连接
     * @author aaron
     */
    private function connect()
    {
        return $this->db;
    }
    
    /**
     * 运行Sql语句,不返回结果集
     * @author eric
     * @param string $sql 
     * @return mysqli_result|bool
     */
    public function runSql($sql)
    {
        $dbconnect = $this->connect();
        if ($dbconnect === false) {
            return FALSE;
        }
        // 成功:TRUE 失败:FALSE
        $res = mysqli_query($dbconnect,$sql);
        
        // 保存错误
        $this->save_error($dbconnect);
        
        return $res;
    }
    
    /**
     * 获取受影响的行数
     * @author aaron
     * @param string $sql 
     * @return int
     */
    public function affectedRows()
    {
        $dbconnect = $this->connect();
        if ($dbconnect === false) {
            return FALSE;
        }
        $res = mysqli_affected_rows($dbconnect);
        // 保存错误
        $this->save_error($dbconnect);
        
        return $res;
    }
    
 
    /**
     * 运行Sql,以多维数组方式返回结果集
     * @author aaron
     * @param string $sql 
     * @return array 成功返回数组，失败时返回false
     */
    public function getData($sql)
    {
        // 返回数组
        $data = Array();
        // 初始化连接
        $dbconnect = $this->connect();
        if($dbconnect === false){
            return FALSE;
        }
        // 执行sql语句 返回mysqli_result对象
        $result = mysqli_query($dbconnect,$sql);
        $this->save_error($dbconnect);
        if(is_bool($result)){
            return $result;
        }else{
            while($array = mysqli_fetch_array($result, MYSQL_ASSOC)){
                $data[] = $array;
            }
        }
        // 关闭 mysqli_result
        mysqli_free_result($result); 
 
        if(count($data)>0){
            return $data;
        }else{
            return NULL;   
        }
    }
    
    
     
    /**
     * 运行Sql,以数组方式返回结果集第一条记录
     * @author aaron
     * @param string $sql 
     * @return array 成功返回数组，失败时返回false
     */
    public function getLine($sql)
    {
        $data = $this->getData($sql);
        if ($data) {
            return @reset($data);
        } else {
            return FALSE;
        }
    }
 
    /**
     * 运行Sql,返回结果集第一条记录的第一个字段值
     * @author aaron
     * @param string $sql 
     * @return mixxed 成功时返回一个值，失败时返回false
     */
    public function getVar( $sql )
    {
        $data = $this->getLine($sql);
        if ($data) {
            return $data[@reset(@array_keys($data))];
        } else {
            return FALSE;
        }
    } 
    
    
    /**
     * 获取新增的id
     * @author aaron
     * @return int 成功返回last_id,失败时返回false
     */
    public function lastId()
    {
        $id = mysqli_insert_id($this->connect());
        return $id;
    }
    /**
     * 关闭数据库连接
     * @author aaron
     * @return bool
     */
    public function closeDb()
    {
        @mysqli_close($this->connect());
    }
    
    
    public function errno()
    {
        return $this->errno;
    }
    public function errmsg()
    {
        return $this->error;
    }
    private function save_error($dbconnect)
    {
        $this->errno = mysqli_errno($dbconnect);
        $this->error = mysqli_error($dbconnect);
    }
}

?>

继承上面的类，继续封装 增删改的操作：

 $value) {
        $fileds[] = "`".$key."`";
        $values[] = "'".$value."'";
    }

    $str_fileds = implode(',', $fileds);
    $str_values = implode(',', $values);
    $sql = "insert into `".$table_name."` (".$str_fileds.") values(".$str_values.")";
    $result = $db->runSql($sql);
    
    if($boo){
        // 获取新增后的ID
        $result = $db->lastId();
    }

    return $result;
}


/**
 * 修改
 * @author aaron
 * @param object    $db             数据库连接
 * @param string    $table_name     表名
 * @param array     $params         array('列名'=》$value)
 * @param array     $conditions     array('列名'=》$value)
 * @return bool true 修改成功； false 修改失败
 */
function db_update($db, $table_name, $params, $conditions)
{    
    // 更改的值
    $arr_params = array();
    foreach ($params as $key => $value) {
        if(is_null($value)){
            $arr_params[] = "`".$key."` = NULL";
        }else{
            $arr_params[] = "`".$key."` = '".$value."'";
        }
    }
    // 更改条件
    $arr_conditions = array();
    foreach ($conditions as $key => $value) {
        $arr_conditions[] = "`".$key."` = '".$value."'";
    }
    
    $str_fileds = implode(',', $arr_params);
    $str_where = implode(' and ', $arr_conditions);

    $sql = "update `".$table_name."` set ".$str_fileds." where ".$str_where;
    $res = $db->runSql($sql);

    return $res;
}

/**
 * 删除
 * @author aaron
 * @param object    $db             数据库连接
 * @param string    $table_name     表名
 * @param array     $conditions     array('列名'=》$value)
 * @return bool 操作是否成功
 */
function db_delete($db, $table_name, $conditions)
{    
    // 更改条件
    $arr_conditions = array();
    foreach ($conditions as $key => $value) {
        $arr_conditions[] = "`".$key."` = '".$value."'";
    }
    $str_where = implode(' and ', $arr_conditions);
    
    $sql = "delete from `".$table_name."` where ".$str_where;
    $res = $db->runSql($sql);

    return $res;
}

简单的写了点东西，封装数组的方式 传入 db_insert 、db_update、db_delete，select操作个人还是喜欢直接 select语句来的比较方便、容易操作