The following code works fine and display student enrollment records on the page. Right before the table element, I have 3 buttons to filter out records based on the button that was clicked. In the controller, I added a function IsEnrolled. The first button “All” calls Index and it works fine. The second button “Enrolled” call IsEnrolled function and I get an error:

The view ‘IsEnrolled’ or its master was not found or no view engine supports the searched locations.

What do I need to do to make it to work?

@model IEnumerable<MyProject.Models.MyModel>

@{
    ViewBag.Title = "Index";
}

<h2>Class Enrollment</h2>

<form method="get" action="@Url.Action(" Index")">
        <p>
            Search by Last Name: <input type="text" name="searchString" value="@ViewData[" CurrentFilter"]" />
            <input type="submit" value="Search" class="btn btn-default" /> @*| <a asp-action="Index">Go Back</a>*@
            @Html.ActionLink("Show All", "Index")
        </p>

        <div class="btn-group" role="group" aria-label="Filter by IsFeatured">
            <button type="button" class="btn btn-primary @((ViewBag.IsFeaturedFilter == null) ? " active" : "" )"
                    onclick="location.href='@Url.Action(" Index", "MyModel" )'">
                All
            </button>
            <button type="button" class="btn btn-primary @((ViewBag.IsFeaturedFilter == true) ? " active" : "" )"
                    onclick="location.href='@Url.Action(" IsEnrolled "MyModel" , new { isFeaturedFilter=true })'">
                Enrolled             

</button>             

<button type="button" class="btn btn-primary @((ViewBag.IsFeaturedFilter == false) ? " active" : "" )"
                    onclick="location.href='@Url.Action(" Index", "MyModel" , new { isFeaturedFilter=false })'">
                Not Enrolled

             </button>         </div>      </form>


    <table class="table">
        <tr style="background-color:lightsteelblue; color:navy">
            <th>
                @Html.DisplayNameFor(model => model.StudentId)
            </th>
            <th>
                @Html.DisplayNameFor(model => model.FirstName)
            </th>
            <th>
                @Html.DisplayNameFor(model => model.EnrollmentStatus)
            </th>
            
        </tr>

        @{
            int i = 0;
        }

        <tr class="@rowColor">
            <td>
                @Html.DisplayFor(modelItem => item.StudentID)
            </td>
            <td>
                @Html.DisplayFor(modelItem => item.FirstName, new { @class = "form-control", @readonly = "readonly" })
            </td>
            <td>
                @Html.DisplayFor(modelItem => item.EnrollmentStatus)
            </td>
        </tr>
        }

    </table>

    <br />

Code:

namespace MyProject.Controllers
{
    public class StudentsController : Controller
    {
        private cnStudents db = new cnStudents();

        public ActionResult Index(string sortOrder, string searchString)
        {
            var subjects = from m in db.Students select m;

            ViewData["NameSortParm"] = String.IsNullOrEmpty(sortOrder) ? "name_desc" : "";
            ViewData["DateSortParm"] = sortOrder == "Date" ? "date_desc" : "Date";

            switch (sortOrder)
            {
                case "name_desc":
                    subjects = subjects.OrderByDescending(s => s.FirstName);
                    break;


                    subjects = subjects.OrderByDescending(s => s.LastName);
                    break;

                case "Date":
                    subjects = subjects.OrderBy(s => s.EnrollmentDate);
                    break;
            }

            if (!String.IsNullOrEmpty(searchString))
            {
                if (!string.IsNullOrEmpty(searchString))
                {

subjects = subjects.Where(s => s.LastName == searchString

|| s.FirstName.Contains(searchString)

|| s.FirstName.ToString().Contains(searchString)

);

}

}

ViewBag.CurrentSearch = searchString;

return View(subjects);

}

public ActionResult IsEnrolled(bool? isFeaturedFilter = null)

{

var students = from m in db.Students select m;

students = students.Where(s => s.IsEnrolled == isFeaturedFilter);

ViewBag.IsFeaturedFilter = isFeaturedFilter; 

return View(subjects);

}

public ActionResult SearchAct()

{

return View();

}

[HttpPost]

public ActionResult SearchAct(string nameToFind)

{

ViewBag.SearchKey = nameToFind;

return View();

}

protected override void Dispose(bool disposing)

{

if (disposing)

{

db.Dispose();

}

base.Dispose(disposing);

}

}

}