How to pass complex object to ASP.NET WebApi GET from jQuery ajax call?

Question

I have the following complex object in JavaScript which contains filter options

var filter={caseIdentifiter:\'GFT1\',userID:\'2\'};

which I

Answer 1

If you append json data to query string, and parse it later in web api side. you can parse complex object. It's useful rather than post json object style. This is my solution.

//javascript file 
var data = { UserID: "10", UserName: "Long", AppInstanceID: "100", ProcessGUID: "BF1CC2EB-D9BD-45FD-BF87-939DD8FF9071" };
var request = JSON.stringify(data);
request = encodeURIComponent(request);

doAjaxGet("/ProductWebApi/api/Workflow/StartProcess?data=", request, function (result) {
    window.console.log(result);
});

//webapi file:
[HttpGet]
public ResponseResult StartProcess()
{
    dynamic queryJson = ParseHttpGetJson(Request.RequestUri.Query);
        int appInstanceID = int.Parse(queryJson.AppInstanceID.Value);
    Guid processGUID = Guid.Parse(queryJson.ProcessGUID.Value);
    int userID = int.Parse(queryJson.UserID.Value);
    string userName = queryJson.UserName.Value;
}

//utility function:
public static dynamic ParseHttpGetJson(string query)
{
    if (!string.IsNullOrEmpty(query))
    {
        try
        {
            var json = query.Substring(7, query.Length - 7); //seperate ?data= characters
            json = System.Web.HttpUtility.UrlDecode(json);
            dynamic queryJson = JsonConvert.DeserializeObject<dynamic>(json);

            return queryJson;
        }
        catch (System.Exception e)
        {
            throw new ApplicationException("can't deserialize object as wrong string content！", e);
        }
    }
    else
    {
        return null;
    }
}

Answer 2

After finding this StackOverflow question/answer

Complex type is getting null in a ApiController parameter

the [FromBody] attribute on the controller method needs to be [FromUri] since a GET does not have a body. After this change the "filter" complex object is passed correctly.