If criteria not met redirect to different Razor Page from public async Task OnGetAsync()

Question

I am new to the "async" and "task" stuff. I can't seem to get working a simple if{} else{} inside the OnGetAsync().

public async Task OnGetAsync()
{
    if (HttpContext.Session.GetString("LoggedStatus") != null)
    {
        //KEEP GOING
    Accounts = await _context.Accounts.ToListAsync();
    }
    else
    {
    RedirectToPage("./Index");
    } 
}

The error I get is from the Accounts page, which I am trying to avoid even going near by using the "RedirectToPage("./Index")" which is my Home page. I tried putting "return" word in front of RedirectToPage but it turns red when I do that. Also, if first condition is met (there is a value in the Session object) the Accounts pages shows up with no errors. So, I'm pretty sure the problem is in my attempt to redirect in the "else" statment.

NullReferenceException: Object reference not set to an instance of an object.
OESAC.Pages.Accounts.Pages_Accounts_Index.ExecuteAsync() in Index.cshtml
+
        @foreach (var item in Model.Accounts)

The error above is in Accounts right where it loops thru and displays rows. I'm not sure why it even gets to the Accounts.chstml.

Answer 1

You need to use Task<IActionResult> in public async Task<IActionResult> OnGetAsync(), combined with a return statement.

public async Task<IActionResult> OnGetAsync()
{
    if (HttpContext.Session.GetString("LoggedStatus") != null)
    {
        //KEEP GOING
        Accounts = await _context.Accounts.ToListAsync();

        return Page();
    }
    else
    {
        return RedirectToPage("./Index");
    } 
}

---

Microsoft's docs has some good read on this here:

• https://learn.microsoft.com/en-us/aspnet/core/razor-pages/?view=aspnetcore-2.2&tabs=visual-studio

---

Based on a comment, you can run this w/o async.

public IActionResult OnGet()
{
    if (HttpContext.Session.GetString("LoggedStatus") != null)
    {
        //KEEP GOING
        Accounts = _context.Accounts.ToList();

        return Page();
    }
    else
    {
        return RedirectToPage("./Index");
    } 
}