Currently I'm using the helper methods outlined here to return some JSON from my .ashx: http://weblogs.asp.net/scottgu/archive/2007/10/01/tip-trick-building-a-tojson-extension-method-using-net-3-5.aspx

Problem is, I get [ and ] wrapped around my JSON which is malformed...jQuery cannot pick it up in the callback:

[{"ImageTag":"<img src="http://www.xxx.com/image/473.jpg" alt="">"},{"ImageTag":"<img src="http://www.xxx.com/image/485.jpg" alt="">"}]

So I don't know why I get brackets around this.  Here is my implementation:

    private void GetImagesJSON(HttpContext context)
    {
        context.Response.ContentType = "text/plain";
        context.Response.Charset = Encoding.UTF8.ToString();
        
        int i = 1;

        List<Product> products = GetTestProducts();
        List<CtImageList> imageList = new List<CtImageList>();
        
        foreach(Product p in products)
        {
            string imageTag = HttpUtility.HtmlEncode(string.Format(@"<img src=""{0}"" alt="""">", ImageUrl(p.Image, false)));
            
            imageList.Add(new CtImageList{ImageTag = imageTag});
            i++;
        }

        string jsonString = imageList.ToJSON();
        context.Response.Write(jsonString);
    }

[ and ] is proper JSON array notation. The problem is in your consuming code.