How to send data & file by json and Ajax to Controller Mvc?

jQuery:-

$(document).on("click", ".save-visa-details", function (e) 

{     

e.preventDefault(); 

var json_obj = { "visa": [] };     

$(".table .js-visa").each(function (index, element) { 

var row = $(this).attr("data-row"); 

if (typeof row != "undefined" && row != "") {

 var visajsonObject = { "employee_id": "", "visa_country": "", "visa_type": "", "visa_entrytype": "", "visa_startdate": "", "visa_expiredate": "", "visa_copy": "" }; 

visajsonObject.employee_id = 454543; var fileInput = new FormData($(".js-course-" + row + " .js-visa-copy").get(0));   

jsonObject.visa_copy = fileInput;             

 visajsonObject.visa_country = $(".js-visa-" + row + " .country").val();  

visajsonObject.visa_type = $(".js-visa-" + row + " .visatype").val(); 

visajsonObject.visa_entrytype = $(".js-visa-" + row + " .visamemberentrytype").val();    

visajsonObject.visa_startdate = $(".js-visa-" + row + " .js-visa-start-date").val();

visajsonObject.visa_expiredate = $(".js-visa-" + row + " .js-visa-expire-date").val(); 

json_obj.visa.push(visajsonObject); } });  

    $.ajax({  

 type: "POST",    

  url: "@Url.Action("SaveEmployeeVisa")",    

 dataType: "json", 

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

 data: JSON.stringify(json_obj),  

 success: function (data) {        

 alert("Visa details are register successfully"); }

 });

  });

Model

public class Visa {
public int employee_id { get; set; } 
public string visa_country { get; set; }
public string visa_type { get; set; } 
public string visa_entrytype { get; set; } 
public DateTime? visa_startdate { get; set; } 
public DateTime? visa_expiredate { get; set; } 
public HttpPostedFileBase visa_copy { get; set; } 
}

Controller:

[HttpPost] 
public ActionResult SaveEmployeeVisa(List visa) 
{ 
if (_cm.SaveEmployeeVisaDetails(visa)) 
{ return Json(""); 
} 
else 
{ 
eturn Json("Not saved, Went to some bug");
 }  
}