Query JSON using LINQ

You can deserialize the JSON into a dynamic object, and then use Linq to Objects:

    [TestMethod]    public void TestMethod1()    {        const string json = @"""Items"": [{""Result"": {  ""Id"": ""191e24b8-887d-e111-96ec-000c29128cee"",  ""Name"": ""Name"",  ""StartDate"": ""2012-04-03T00:00:00+01:00"",  ""EndDate"": null,  ""Status"": {    ""Name"": ""Active"",    ""Value"": 5  },  ""Client"": {    ""Id"": ""35ea10da-b8d5-4ef8-bf23-c829ae90fe60"",    ""Name"": ""client Name"",    ""AdditionalItems"": {}  },  ""ServiceAgreement"": {    ""Id"": ""65216699-a409-44b0-8294-0e995eb05d9d"",    ""Name"": ""Name"",    ""AdditionalItems"": {      ""ScheduleBased"": true,      ""PayFrequency"": {        ""Id"": ""981acb72-8291-de11-98fa-005056c00008"",        ""Name"": ""Weekly"",        ""AdditionalItems"": {}      },      ""PayCycle"": [        {          ""Name"": ""Schedule Based"",          ""ScheduleBased"": true,          ""SelfBilling"": false,          ""Id"": ""a8a2ecc4-ff79-46da-a135-743b57808ec3"",          ""CreatedOn"": ""2011-09-16T23:32:19+01:00"",          ""CreatedBy"": ""System Administrator"",          ""ModifiedOn"": ""2011-09-16T23:32:19+01:00"",          ""ModifiedBy"": ""System Administrator"",          ""Archived"": false        }      ]    }  }}}]";        dynamic data = System.Web.Helpers.Json.Decode("{" + json + "}");        var result = from i in (IEnumerable<dynamic>)data.Items                     where i.Result.ServiceAgreement.AdditionalItems.ScheduleBased == true                     select new                            {                                i.Result.Client.Name,                                i.Result.Client.Id                            };        Assert.AreEqual(1, result.Count());        Assert.AreEqual("client Name", result.First().Name);        Assert.AreEqual("35ea10da-b8d5-4ef8-bf23-c829ae90fe60", result.First().Id);    }

Note that I had to add brackets { and } around your example json string, or else the .NET json parser doesn't like it.

To start off, I'm not familiar with writing LINQ/LAMBDA using this format ["some"]["thing"].My first step would be to create some classes/objects to house the data in to ease creating any code afterwards.

e.g.

public class Result{    public Guid Id { get; set; }     public string Name { get; set; },    public DateTime StartDate  { get; set; }    //you get the idea}

But possibly try the following?

    var result = from p in data["Data"]["Items"].Children()                 where (bool)p["Result"]["ServiceAgreement"]["AdditionalItems"]["ScheduleBased"] == true                    && (p["Result"]["ServiceAgreement"]["AdditionalItems"]["PayCycle"]).Where(o => o.["ScheduleBased"] == true)                 select new                 {                     Name = (string)p["Result"]["Client"]["Name"],                     Id = (string)p["Result"]["Client"]["Id"]                 };