parsing by Linq to JSON
{"SearchResults":[{"PageCount":"1"},
{"SEARCHVAL":"Result","CATEGORY":"Category1","X":"1","Y":"2"},
{"SEARCHVAL":"AnotherResult","CATEGORY":"Category1","X":"2","Y":"2"}]}

WebClient client = new WebClient();
client.OpenReadCompleted +=
    new OpenReadCompletedEventHandler(client_OpenReadCompleted);
client.OpenReadAsync(uri);

JsonObject searchResults = (JsonObject)JsonValue.Load(e.Result);

public class SearchResult
 {
      public string SearchValue {get; set;}
      public string Category {get; set;}
      public string X {get; set;}
      public string Y {get; set;}
 }

var resultList = ((JsonArray)searchResults["SearchResults"])
   .OfType<JsonObject>()
   .Where(o => o.ContainsKey("SEARCHVAL"))
   .Select(o => new SearchResult() {
       SearchValue = o["SEARCHVALUE"],
       Category = o["CATEGORY"].
       X = o["X"],
       Y = o["Y"]
   }).ToList();