/**

     * [array_to_sql 根据数组key和value拼接成需要的sql]

     * @param  [type] $array   [key, value结构数组]

     * @param  string $type    [sql类型insert,update]

     * @param  array  $exclude [排除的字段]

     * @return [string]          [返回拼接好的sql]

     */

    function array_to_sql($array, $type='insert', $exclude = array()){

        $sql = '';

        if(count($array) > ){

            foreach ($exclude as $exkey) {

                unset($array[$exkey]);//剔除不要的key

            }

            if('insert' == $type){

                $keys = array_keys($array);

                $values = array_values($array);

                $col = implode("`, `", $keys);

                $val = implode("', '", $values);

                $sql = "(`$col`) values('$val')";

            }else if('update' == $type){

                $tempsql = '';

                $temparr = array();

                foreach ($array as $key => $value) {

                    $tempsql = "'$key' = '$value'";

                    $temparr[] = $tempsql;

                }

                $sql = implode(",", $temparr);

            }

        }

        return $sql;

    }