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;
	}