bind a viewdata inside dropdown list

Question

i wanna bind a viewdata inside dropdown list ,
i use this way

@Html.DropDownListFor(model => model.First().KEYWORD_NAME, ViewData["KEYWORD"] as IEnumerable<SelectListItem>, "Select Company Name", new { @class = "form-control" })

but i have this error :

System.ArgumentNullException: 'Value cannot be null.

Parameter name: source

i don't have any parameter with name source ?
i debug the project and i checked that the view data have data inside it

how i can fix it ?

Sachin Singh · Answer

Please Follow the below code @Html.DropDownListFor(x => x.AProperty, new SelectList((IEnumerable)ViewData[ "taskStatusList" ], "Value" , "Text" ), new {@ class = "myClass" }) public ActionResult Index() { List taskStatus = new List (); taskStatus.Add( new SelectListItem { Text = "New" , Value = "0" }); taskStatus.Add( new SelectListItem { Text = "InProcess" , Value = "1" }); taskStatus.Add( new SelectListItem { Text = "OnHold" , Value = "2" }); taskStatus.Add( new SelectListItem { Text = "Complete" , Value = "3" }); taskStatus.Add( new SelectListItem { Text = "Closed" , Value = "4" }); ViewData[ "taskStatusList" ] = taskStatus; return View(); } public class TestModel { public string AProperty { get ; set ; } }

Mageshwaran R · Answer

Hi, please try this code: Controller: Using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.Mvc; namespace MCVApp.Controllers { public class HomeController : Controller { public ActionResult Index() { List Emp = new List (); Emp.Add( new SelectListItem { Text = "" , Value = "0" }); Emp.Add( new SelectListItem { Text = "Akash" , Value = "1" }); Emp.Add( new SelectListItem { Text = "Karthik" , Value = "2" }); Emp.Add( new SelectListItem { Text = "Giri" , Value = "3" }); Emp.Add( new SelectListItem { Text = "Risheb" , Value = "4" }); ViewData[ "EmpName" ] = Emp; return View(); } } } Razor Page: @using System.Web.Mvc @using System.Collections @{ ViewBag.Title = "Home Page" ; } @Html.DropDownList("EmpName", new SelectList((IEnumerable)ViewData["EmpName"], "Value", "Text"))

Jignesh Kumar · Answer

Hi, @Html.DropDownListFor(x => x.AProperty, new SelectList((IEnumerable)ViewData[ "taskStatusList" ], "ValueFieldName" , "TextName" , "Please Select" ), new {@ class = "myClass" }) Note : ValueFieldName, TextName will be your filed name ViewData["taskStatusList"]