PHP：JSON字符串转换为中文，中文转换为JSON字符串

    /**
         * 中文转换为JSON字符串
         * @param $chinese_str 中文：可以包含中文字母数字
         * @return string
         */
        function json_encode($chinese_str)
        {
                $chinese_str = iconv('UTF-8', 'UCS-2', $chinese_str);
                $len = strlen($chinese_str) - 1;
                $str = '';
                for ($i = 0; $i < $len; $i = $i + 2)
                {
                        $c1 = $chinese_str[$i];
                        $c2 = $chinese_str[$i + 1];
                        $unicode1=ord($c1);
                        $unicode2=ord($c2);
                        if ($unicode1)
                        {    // 两个字节的文字
                                $unicode1='\u'.base_convert($unicode1, 10, 16);
                                $unicode2=base_convert($unicode2, 10, 16);
                                if(in_array($unicode2,array('a','b','c','d','e','f'))){
                                        $unicode2='0'.$unicode2;
                                }
                                $str.=$unicode1.$unicode2;
                        }else{
                                $str.=$c2;
                        }
                }
                return $str;
        }


        /**
         * JSON字符串转换为中文
         * @param $json_str JSON字符串
         * @return string
         */
        function json_decode($json_str)
        {
                // 转换编码，将JSON字符串转换成可以浏览的utf-8编码
                $pattern = '/([\w]+)|(\\\u([\w]{4}))/i';
                preg_match_all($pattern, $json_str, $matches);
                $chinese_str = '';
                if (!empty($matches))
                {
                        $count=count($matches[0]);
                        for ($j = 0; $j < $count; $j++)
                        {
                                $str = $matches[0][$j];
                                if (strpos($str, '\\u') === 0)
                                {
                                        $code = base_convert(substr($str, 2, 2), 16, 10);
                                        $code2 = base_convert(substr($str, 4), 16, 10);
                                        $c = chr($code).chr($code2);
                                        $c = iconv('UCS-2', 'UTF-8', $c);
                                        $chinese_str .= $c;
                                }
                                else
                                {
                                        $chinese_str .= $str;
                                }
                        }
                }
                return $chinese_str;
        }