Saturday, December 22, 2007

Quick and Dirty JSON

So you want to write a JSON service for your Silverlight application? Basically this entire thing is a giant hack. first JSON is just the string syntax for JavaScript so it is not like a real protocol of course I get a bit of heart burn calling 'SOAP' a real protocol but really a JavaScript array defintion being a 'protocol' you must admit is a bit of a stretch but ok I can go with it.
Anyway so quick a dirty in your 'Silverlight' web site project in visual studio you can create a JSON service out of any ASPX page. First 'create' your ASPX page. then remove everything so it looks like this:

< % @ Page Language="C#" AutoEventWireup="true" CodeFile="JSON.aspx.cs" Inherits="JSON" % >
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="JSON.aspx.cs" Inherits="JSON" %>

note that 'JSON' is just what I happened to call this page.
so then just right click on the page and click view code. You'll see that you have basically one method 'Page_Load'. here basically we just need to write out whatever it is we need in the form of a javascript array. So for example here is a very simple one:

StringBuilder JSON = new StringBuilder();

string ItemDelimter = string.Empty;

JSON.Append(ItemDelimter + "\"1\" : \"john doe\" ");

ItemDelimter = " , ";

JSON.Append(ItemDelimter + "\"2\" : \"jill doe\" ");

JSON.Append(ItemDelimter + "\"3\" : \"jane doe\" ");

JSON.Append(ItemDelimter + "\"4\" : \"jared doe\" ");

JSON.Append(ItemDelimter + "\"5\" : \"jeff doe\" ");

Response.Write("[ { " + JSON.ToString() + " } ] ");


Note that you'll need to add System.Text for the above code but you can basically generate the out put anyway you want and accept input parameters as query string values.


  1. Hi David,

    Is there any special reason why you're not using the /js proxy to as standard ASMX page that comes with ASP.NET Ajax and that exposes automagically the output of your SOAP service as a JSON result?

    Are you also aware that a JSON serializer now comes with WCF3.5?

    Christophe Lauer --

  2. mostly because this was for a Silverlight 64bit Vista Sidebar gadget that can't use any AJAX and I didn't want to spend more then 5 minutes making it work... And only Silverlight 1.0 can be used for the project and no upgrades to the server... So I guess I should cavate this with the reason for not using ajax or something a bit more clean. The key thing was to make it work and complete the app given the circumstance as fast as possible. Hence the hacking :)

  3. ok ok, I give. JSON is a bad idea entirely in a sidebar gadget, in vista using silverlight... it just doens't seem practical so I'm going back to some nice old fashioned SOAP/XML.

    more ranting on this topic at: