How can i solve my this issue in MVC grid Delete Controller - model-view-controller

Question

Controller:
public ActionResult Delete(int id)
{
Student _std = new Student();
var abc = _dbcon.StudentList.Where(c => c.Roll_ID.Equals(id)).SingleOrDefault();
_dbcon.StudentList.Remove(abc);
_dbcon.SaveChanges();
return View("Test");
}
This is my view and the error comes at foreach loop
View:
#foreach (StudentViewModel _EachStd in #Model.StudentList)
{
<tr>
<td> #_EachStd.Roll_ID</td>
<td> #_EachStd.Name</td>
<td> #_EachStd.Maths</td>
<td> #_EachStd.Urdu</td>
<td> #_EachStd.English</td>
<td>#_EachStd.ObtainNumber</td>
<td>#_EachStd.Percentage</td>
<td> #_EachStd.Grade</td>
<td>#Html.ActionLink("Edit", "Edit", "Home", new {id= #_EachStd.Roll_ID },null)</td>
<td>#Html.ActionLink("Delete", "Delete", "Home", new { id = #_EachStd.Roll_ID }, null)</td>
</tr>
}
</tbody>
</table>
I got Null Error exception, but after refresh i got the record delete. But why the error occur I dont get It.Whenever i run this code my Edit controller is working correctly but my Delete controller is not working correctly, and error is occur like there is "Null erroe exception"

Answer 1

error is occur like there is "Null erroe exception"
You mean a NullReferenceException? That would mean something is null that you're trying to use as though it has a value.
This is my view and the error comes at foreach loop
So then something on this line is null?:
#foreach (StudentViewModel _EachStd in #Model.StudentList)
The only thing you're trying to dereference on that line is Model. So it follows that Model is null. Are you passing a model to your view?
return View("Test");
No, you are not. You need to pass a model to your view in order to use that model within your view.
As an aside, returning a view from this delete operation probably isn't the way to go in the first place. Consider that the user would now be on the URL /Home/Delete and viewing it as a page. This would quickly get confusing for both the user and your code.
Instead of returning a view, especially one without a model, redirect the user to the action which builds the model and displays the view. Which in your code could be something as simple as:
return RedirectToAction("Test");