С появлением jquery стало очень удобно с  работать Ajax. И теперь при работе с Grid я обращаюсь к методам контролера, которые возвращает информацию в Json формате. Не знаю правильно ли это, но очень удобно. Но в таком подходе есть свои проблемы. По умолчанию количество символов передаваемых таким методом ограничено. И сервер выдает ошибку:

[InvalidOperationException: Error during serialization or deserialization using the JSON JavaScriptSerializer. The length of the string exceeds the value set on the maxJsonLength property.]    System.Web.Script.Serialization.JavaScriptSerializer.Serialize(Object obj, StringBuilder output, SerializationFormat serializationFormat) +551497    System.Web.Script.Serialization.JavaScriptSerializer.Serialize(Object obj, SerializationFormat serializationFormat) +74    System.Web.Script.Serialization.JavaScriptSerializer.Serialize(Object obj) +6    System.Web.Mvc.JsonResult.ExecuteResult(ControllerContext context) +341    System.Web.Mvc.ControllerActionInvoker.InvokeActionResult(ControllerContext controllerContext, ActionResult actionResult) +10    System.Web.Mvc.<>c__DisplayClass14.<InvokeActionResultWithFilters>b__11() +20    System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func`1 continuation) +251    System.Web.Mvc.<>c__DisplayClass16.<InvokeActionResultWithFilters>b__13() +19    System.Web.Mvc.ControllerActionInvoker.InvokeActionResultWithFilters(ControllerContext controllerContext, IList`1 filters, ActionResult actionResult) +178    System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +314    System.Web.Mvc.Controller.ExecuteCore() +105    System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +39    System.Web.Mvc.ControllerBase.System.Web.Mvc.IController.Execute(RequestContext requestContext) +7    System.Web.Mvc.<>c__DisplayClass8.<BeginProcessRequest>b__4() +34    System.Web.Mvc.Async.<>c__DisplayClass1.<MakeVoidDelegate>b__0() +21    System.Web.Mvc.Async.<>c__DisplayClass8`1.<BeginSynchronous>b__7(IAsyncResult _) +12    System.Web.Mvc.Async.WrappedAsyncResult`1.End() +59    System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +44    System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +7    System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +8682542    System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155 

Поискал в интернете, и нашел решение проблемы.

Ошибка находится внутри обращения MVC к BCL.

if (Data != null) {
    JavaScriptSerializer serializer = new JavaScriptSerializer();
    response.Write(serializer.Serialize(Data));
}
Во время сериализации сервер падает.

public string Serialize(object obj) {
    return Serialize(obj, SerializationFormat.JSON);
}

private string Serialize(object obj, SerializationFormat serializationFormat) {
    StringBuilder sb = new StringBuilder();
    Serialize(obj, sb, serializationFormat);
    return sb.ToString();
}

internal void Serialize(object obj, StringBuilder output, SerializationFormat serializationFormat) {
    SerializeValue(obj, output, 0, null, serializationFormat);
    // DevDiv Bugs 96574: Max JSON length does not apply when serializing to Javascript for ScriptDescriptors
    if (serializationFormat == SerializationFormat.JSON && output.Length > MaxJsonLength) {
        throw new InvalidOperationException(AtlasWeb.JSON_MaxJsonLengthExceeded);
    }
}
 

Т.е. стоит ограничение в 96574 символов. Мы должны реализовать наш собственный ActionResult, который будет генерировать JSON любого размера. Код:

using System;
using System.Web.Script.Serialization;

namespace System.Web.Mvc
{
    public class LargeJsonResult : JsonResult
    {
        const string JsonRequest_GetNotAllowed = "This request has been blocked because sensitive information could be disclosed to third party web sites when this is used in a GET request. To allow GET requests, set JsonRequestBehavior to AllowGet.";
        public LargeJsonResult()
        {
            MaxJsonLength = 1024000;
            RecursionLimit = 100;
        }

        public int MaxJsonLength { get; set; }
        public int RecursionLimit { get; set; }

        public override void ExecuteResult( ControllerContext context )
        {
            if( context == null )
            {
                throw new ArgumentNullException( "context" );
            }
            if( JsonRequestBehavior == JsonRequestBehavior.DenyGet &&
                String.Equals( context.HttpContext.Request.HttpMethod, "GET", StringComparison.OrdinalIgnoreCase ) )
            {
                throw new InvalidOperationException( JsonRequest_GetNotAllowed );
            }

            HttpResponseBase response = context.HttpContext.Response;

            if( !String.IsNullOrEmpty( ContentType ) )
            {
                response.ContentType = ContentType;
            }
            else
            {
                response.ContentType = "application/json";
            }
            if( ContentEncoding != null )
            {
                response.ContentEncoding = ContentEncoding;
            }
            if( Data != null )
            {
                JavaScriptSerializer serializer = new JavaScriptSerializer() { MaxJsonLength = MaxJsonLength, RecursionLimit = RecursionLimit };
                response.Write( serializer.Serialize( Data ) );
            }
        }
    }
}

Теперь мы можем использовать этот класс:

return new LargeJsonResult() { Data = output, MaxJsonLength = int.MaxValue };

Так же нужно подправить web.config

<system.web.extensions>
    <scripting>
      <webServices>
        <jsonSerialization maxJsonLength="2147483644"  />
      </webServices>
    </scripting>
  </system.web.extensions>