Returning JSON object from an ASP.NET page

In your Page_Load you will want to clear out the normal output and write your own, for example:

string json = "{\"name\":\"Joe\"}";
Response.Clear();
Response.ContentType = "application/json; charset=utf-8";
Response.Write(json);
Response.End();

To convert a C# object to JSON you can use a library such as Json.NET.

Instead of getting your .aspx page to output JSON though, consider using a Web Service (asmx) or WCF, both of which can output JSON.

no problem doing it with asp.... it's most natural to do so with MVC, but can be done with standard asp as well.

The MVC framework has all sorts of helper classes for JSON, if you can, I'd suggest sussing in some MVC-love, if not, you can probably easily just get the JSON helper classes used by MVC in and use them in the context of asp.net.

edit:

here's an example of how to return JSON data with MVC. This would be in your controller class. This is out of the box functionality with MVC--when you crate a new MVC project this stuff gets auto-created so it's nothing special. The only thing that I"m doing is returning an actionResult that is JSON. The JSON method I'm calling is a method on the Controller class. This is all very basic, default MVC stuff:

public ActionResult GetData()
{
    var data = new { Name="kevin", Age=40 };
    return Json(data, JsonRequestBehavior.AllowGet);
}

This return data could be called via JQuery as an ajax call thusly:

$.get("/Reader/GetData/", function(data) { someJavacriptMethodOnData(data); });