由于json_encode函數(shù)需要php5.20以上版本才支持，php不支持json_encode如何也用上json的功能呢？有沒(méi)有什么替代函數(shù)，替代函數(shù)是沒(méi)有的，不過(guò)有人做了一個(gè)自定義的php_json_encode，使用中會(huì)出現(xiàn)什么樣的問(wèn)題還未可知.

http://www.php.net/manual/zh/function.json-encode.php#74878

[php]
function php_json_encode($arr)
{
??? $json_str = "";
??? if(is_array($arr))
??? {
????? $pure_array = true;
????? $array_length = count($arr);
????? for($i=0;$i????? {
??????? if(! isset($arr[$i]))
??????? {
????????? $pure_array = false;
????????? break;
??????? }
????? }
????? if($pure_array)
????? {
??????? $json_str ="[";
??????? $temp = array();
??????? for($i=0;$i??????? {
????????? $temp[] = sprintf("%s", php_json_encode($arr[$i]));
??????? }
??????? $json_str .= implode(",",$temp);
??????? $json_str .="]";
????? }
????? else
????? {
??????? $json_str ="{";
??????? $temp = array();
??????? foreach($arr as $key => $value)
??????? {
????????? $temp[] = sprintf(""%s":%s", $key, php_json_encode($value));
??????? }
??????? $json_str .= implode(",",$temp);
??????? $json_str .="}";
????? }
??? }
??? else
??? {
????? if(is_string($arr))
????? {
??????? $json_str = """. json_encode_string($arr) . """;
????? }
????? else if(is_numeric($arr))
????? {
??????? $json_str = $arr;
????? }
????? else
????? {
??????? $json_str = """. json_encode_string($arr) . """;
????? }
??? }
??? return $json_str;
}

function json_encode_string($in_str) {
??? mb_internal_encoding("UTF-8");
??? $convmap = array(0x80, 0xFFFF, 0, 0xFFFF);
??? $str = "";
??? for ($i = mb_strlen($in_str)-1; $i>=0; $i--) {
??????? $mb_char = mb_substr($in_str, $i, 1);
??????? if (mb_ereg("(\d+);", mb_encode_numericentity($mb_char, $convmap, "UTF-8"), $match)) {
??????????? $str = sprintf("\u%04x", $match[1]) . $str;
??????? } else {
??????????? $str = $mb_char . $str;
??????? }
??? }
??? return $str;
}

[/php]

json_encode替代函數(shù)php_json_encode