Cannot show the value from ViewBag-CodePudding

I am trying to show the value of ViewBag on my .cshtml page, but the value is always empty. Below is my code:

public async Task<IActionResult> DateCalc( int? department)
{

    ViewBag.DestroyCount = 4; // docDestroyed;
    return RedirectToAction(nameof(Index));
}

This is what I have in my Index.cshtml :

<div >
    <form asp-action="DateCalc" enctype="multipart/form-data">
  <h5 >Documents destroyed by section</h5>
  <div >
       <div >
        <label>Select Department(s)</label>
           @Html.DropDownList("department", (IEnumerable
        <SelectListItem>)ViewBag.department, new{@})
       </div>
       <div></div>

   <br /><br />
    <input type="submit" value="submit"  />
    <p >Documents Destroyed by Section: </p>@Html.Label((string)ViewBag.DestroyCount) 
  </div>
  </form>
</div>

When I click on submit button, I want "Documents Destroyed by Section:" to display 4, but it does not display anything.

This is the line where I am trying to display DestroyCount after clicking on submit button:

@Html.Label((string)ViewBag.DestroyCount)

Any help will be appreciated.

CodePudding user response：

The data for ViewBag.DestroyCount was lost as you perform the redirection as:

public async Task<IActionResult> DateCalc(int? department)
{
    ...
    return RedirectToAction(nameof(Index));
}

The data for ViewBag and ViewData is only lasted within the same request.

According to this