public static function characet($str, $targetCharset)
    {
        if (empty($str)) {
            return $str;
        }

        if (strcasecmp('UTF-8', $targetCharset) != 0) {
            $str = mb_convert_encoding($str, $targetCharset, 'UTF-8');
        }

        return $str;
    }
public static function characet($str, $targetCharset)
    {
        if (empty($str)) {
            return $str;
        }

        if (strcasecmp('UTF-8', $targetCharset) != 0) {
            $str = mb_convert_encoding($str, $targetCharset, 'UTF-8');
        }

        return $str;
    }
public static function characet ( $ str , $ targetCharset ) { if ( empty ( $ str ) ) { return $ str ; } if ( strcasecmp ( 'UTF-8' , $ targetCharset ) != 0 ) { $ str = mb_convert_encoding ( $ str , $ targetCharset , 'UTF-8' ) ; } return $ str ; }
转码字符集转码  仅支持 转码 到 UTF-8
@param string $str
@param string $targetCharset
@return mixed|string
转码字符集转码 仅支持 转码 到 UTF - 8