How to compress JSON responses

Question

I am using a lot of ajax calls to query the database and I get large text (json) responses. I will like to compress the response.

There is a great way of compressing text using javascript in JavaScript implementation of Gzip.

The problem is I want to compress the response on my aspx server and decmpress it with javascript. Therefore I need to run the lzw_encode function on my asp.net server. Should I I translate that function to C# or there is another way?

Using the link above if you dont want to configure IIS or change header you can compress the code on the server with:

C#

    public static string Compress(string s)     {         var dict = new Dictionary<string, int>();         char[] data = s.ToArray();         var output = new List<char>();         char currChar;         string phrase = data[0].ToString();         int code = 256;          for (var i = 1; i < data.Length; i++){             currChar = data[i];             var temp = phrase + currChar;             if (dict.ContainsKey(temp))                                 phrase += currChar;                             else             {                 if (phrase.Length > 1)                                         output.Add((char)dict[phrase]);                                     else                                         output.Add((char)phrase[0]);                                     dict[phrase + currChar] = code;                 code++;                 phrase = currChar.ToString();             }         }          if (phrase.Length > 1)                         output.Add((char)dict[phrase]);                     else                         output.Add((char)phrase[0]);          return new string(output.ToArray());     } 

and on the browser you can decompress it with:

javascript

// Decompress an LZW-encoded string function lzw_decode(s) {     var dict = {};     var data = (s + "").split("");     var currChar = data[0];     var oldPhrase = currChar;     var out = [currChar];     var code = 256;     var phrase;     for (var i = 1; i < data.length; i++) {         var currCode = data[i].charCodeAt(0);         if (currCode < 256) {             phrase = data[i];         }         else {             phrase = dict[currCode] ? dict[currCode] : (oldPhrase + currChar);         }         out.push(phrase);         currChar = phrase.charAt(0);         dict[code] = oldPhrase + currChar;         code++;         oldPhrase = phrase;     }     return out.join(""); }  

Answer 1

Within your server-side response object add a header for GZip, like this:

Response.AddHeader("Content-Encoding", "gzip"); 

Also, you can use the GZipStream class to compress your content, like this:

Response.Filter = new GZipStream(Response.Filter,                                  CompressionMode.Compress);