How to use Postback in ASP.net MVC - html

Question

How to preserve the selected value after postback for that dropdownlist?
I have used two dropdown lists in my application. I need to search the gridview data based on the selected values of dropdownlist. The searched data is displayed in the pagedlist format. But when i move to next page of pagedlist, its displaying the whole grid view data rather than searched data. so any help will be appreciated.
My Model
namespace CCIOfficeServiceManagementSystem.Models
{
public class AirtelManagementModel
{
public long MobileAcNumber { get; set; }
public long AirtelNumber { get; set; }
public int OneTime { get; set; }
public float MonthlyCharges { get; set; }
public float CallCharges { get; set; }
public float ValueAddedServices { get; set; }
public float MobileInternetUsage { get; set; }
public float Roaming{ get; set; }
public float Discounts { get; set; }
public float Taxes { get; set; }
public float TotalCharges { get; set; }
public string WhoUploaded { get; set; }
public DateTime UploadedDate { get; set; }
public DateTime DateOfCreation { get; set; }
public int ImportDateId { get; set; }
public List<MonthListClass> MonthList
{
get;
set;
}
public List<clsYearOfDate> YearList
{
get;
set;
}
}
public class MonthListClass
{
public int MonthSelectedId { get; set; }
public string MonthName { get; set; }
}
public class clsYearOfDate
{
public int YearSelectedId { get; set; }
public string YearOfDate { get; set; }
}
}
My View
#using (Html.BeginForm("ViewDataOfDatabase", "AirtelManagement",FormMethod.Post))
{
<h3>Search by PhoneNumber:#Html.TextBox("SearchString",ViewBag.CurrentFilter as string)</h3>
<p><h3>Year:#Html.DropDownList("Yearitems", (IEnumerable<SelectListItem>)ViewBag.SelectList, "Select Year")</h3>
<h3>Month:#Html.DropDownList("MonthItems", (IEnumerable<SelectListItem>)ViewBag.SelectMonthList, "Select Month")</h3>
<h3>City: #Html.DropDownList("CityNames", (IEnumerable<SelectListItem>)ViewBag.CityList, "Select City")</h3></p>
<p><input type="submit" value="Search" /></p>
<script>
$(document).ready(function () {
$("#Yearitems").change(function () {
//debugger;
//alert($("#Yearitems>option:selected").attr("Value"));
$.ajax({
type: "Post",
url: '#Url.Action("GetMonths","AirtelManagement")',
data: { YearId: $("#Yearitems>option:selected").attr("Value") },
datatype: "Json",
success: function (data) {
//debugger;
$("#MonthItems").html("");
$.each(data, function (index, item) {
$("#MonthItems").append(new Option(item.MonthName, item.MonthSelectedId));
});
},
error: function () {
alert("Select Year");
}
});
});
});
</script>
My controller's action Method
public ActionResult ViewDataOfDatabase(string sortorder, string currentFilter, string searchString, int? page,FormCollection collection)
{
CCIRepository _repository = CCIRepository.CreateRepository();
AirtelManagementModel _Airtelmodel = new AirtelManagementModel();
IEnumerable<CityListClass> CityList = _repository.GetCities();
IEnumerable<SelectListItem> CityListItems = from c in CityList
select new SelectListItem()
{
Value = c.CityName.ToString(),
Text = c.CityName.ToString(),
Selected = c.CityName == Request["CityNames"],
};
ViewBag.CityList = CityListItems;
IEnumerable<clsYearOfDate> SelectList = GetYears();
//IEnumerable<MonthListClass> SelectMonthList = GetMonths(YearId);
IEnumerable<SelectListItem> Yearitems = (from v in SelectList
select new SelectListItem()
{
Value = v.YearSelectedId.ToString(),
Text = v.YearOfDate.ToString(),
Selected = v.YearOfDate == Request["Yearitems"],
});
ViewBag.SelectList = Yearitems;
int DateId=0;
string CityName = string.Empty;
try
{
int SelectedYear = Convert.ToInt16(collection["Yearitems"].ToString());
int SelectedMonth = Convert.ToInt16(collection["MonthItems"].ToString());
CityName = collection["CityNames"].ToString();
DateId = _repository.GetImportDateId(SelectedYear, SelectedMonth);
}
catch(NullReferenceException Ex)
{
}
//IEnumerable<SelectListItem> MonthItems = (from m in SelectMonthList
// select new SelectListItem()
// {
// Value = m.MonthSelectedId.ToString(),
// Text = m.MonthName,
// });
//ViewBag.SelectMonthList = MonthItems;
IEnumerable<SelectListItem> MonthItems = Enumerable.Empty<SelectListItem>();
ViewBag.SelectMonthList = MonthItems;
List<AirtelManagementModel> list = ViewDetails();
ViewBag.CurrentSort = sortorder;
ViewBag.PhoneSortParm = String.IsNullOrEmpty(sortorder) ? "Phone_desc" : "";
if (searchString != null )
{
page = 1;
}
else
{
searchString = currentFilter;
}
//if(searchString!=null)
//{
ViewBag.CurrentFilter = searchString;
var airteldetails = from _model in list
select _model;
if(!String.IsNullOrEmpty(searchString) && DateId!=0 && !String.IsNullOrEmpty(CityName))
{
airteldetails = _repository.FilterAirtelDetails(searchString, DateId, CityName);
int PageSize = 5;
int PageNumber = (page ?? 1);
return View(airteldetails.ToPagedList(PageNumber, PageSize));
}
//airteldetails=airteldetails.OrderByDescending(A=>A.AirtelNumber);
int pageSize = 5;
int pageNumber = (page ?? 1);
//return View(airteldetails.ToList());
return View(airteldetails.ToPagedList(pageNumber, pageSize));
//}
//if (list.Count > 0)
//{
// var airteldetails = from _model in list
// select _model;
// return View(airteldetails.ToPagedList(pageNumber,pageSize));
//}
//else
//{
// ModelState.AddModelError("Error", "No Data found in Database");
// return RedirectToAction("ImportExcelFile", "AirtelManagement");
//}
}