how to pass class and string in ajax call and pass to action

Hi Friends,

I am facing an issue one of development and i tried few but no result so please help on this

my thing is i am passing model(class name AUVmodel) and string from MVC in Ajax call

but when iam trying to pass any one of the two(AUVmodel or string ) iam getting in controller(parameter class obj )

or controller(parameter string strname) working fine

but controller (parameter class, parameter string ) iam getting error.

I want to know how to pass class and string in ajax call and pass to controller (parameter class, parameter string ) respectively

var formFields = "";

formFields = JSON.stringify(AUVModels); // model

$.ajax({

url: actionUrlToDownloadPAPDocument,

data: { AUVModel:formFields, __RequestVerificationToken:antiForgeryToken},

contentType: "application/json; charset=utf-8",

async: false,

type: 'POST',

success: function (response) {

}

});