MVC 5 Increase Max JSON Length in POST Request

Question

I am sending a POST request to an MVC controller with a large amount of JSON data in the body and it is throwing the following:

ArgumentException: Err

Answer 1

So, although this is a rather disagreeable solution, I got around the problem by reading the request stream manually, rather than relying on MVC's model binders.

For example, my method

[HttpPost]
public JsonResult MyMethod (string data = "") { //... }

Became

[HttpPost]
public JsonResult MyMethod () {
    Stream req = Request.InputStream;
    req.Seek(0, System.IO.SeekOrigin.Begin);
    string json = new StreamReader(req).ReadToEnd();
    MyModel model = JsonConvert.DeserializeObject(json);
    // use model...
}

This way I could use JSON.NET and get around the JSON max length restrictions with MVC's default deserializer.

To adapt this solution, I would recommend creating a custom JsonResult factory that will replace the old in Application_Start().