Razor Pages Net Core auto reload partial view on set frequency - ajax

Question

I am still trying to get to grips with Razor Pages for Net Core and seem to be a bit stuck on this. I have my Index.cshtml:
#page
#model IndexModel
<input type="hidden" name="hdnPageSelector" id="hdnIndexPage" />
<div class="text-center">
<p>Welcome to</p>
<h1 class="display-4">"My Web App"</h1>
</div>
<div class="form-row">
<div class="form-group col-md-2">
<partial name="IndexPartials/_Navigation" />
</div>
<div class="form-group col-md-1">
</div>
<div class="form-group col-md-6">
<partial name="IndexPartials/_Body" />
</div>
<div class="form-group col-md-1">
</div>
<div id="refreshMembers" class="form-group col-md-2">
<partial name="IndexPartials/_Members" />
</div>
</div>
Note the last div has an id="refreshMembers".
The partial view (_Members) that is loaded there looks like this:
#model IndexModel
<label>Members</label>
<br />
#{
foreach (ApplicationUser user in Model.AppUsersList)
{
if (user.IsLoggedIn)
{
<label>#user.FirstName #user.LastName </label>
<span class="dot"></span>
}
else
{
<label>#user.FirstName #user.LastName</label>
}
}
}
Within the controller I have a property called:
public IList<ApplicationUser> AppUsersList { get; set; }
And this is populated on OnGetAsync() as follows:
AppUsersList = _userManager.Users.OrderBy(x => x.FirstName).Where(y => y.UserName != currentUser.UserName).ToList();
This is fine, the page loads with the partial view populated as expected. I now want the partial to refresh every 5 seconds so I have put this piece of Javascript/JQuery in place:
$(function () {
setInterval(function () {
$("#refreshMembers").load("/Index?handler=RefreshMembers");
}, 5000);
});
with the following method setup:
public async Task<IActionResult> OnGetRefreshMembers()
{
var currentUser = await _userManager.GetUserAsync(User);
AppUsersList = _userManager.Users.OrderBy(x => x.FirstName).Where(y => y.UserName != currentUser.UserName).ToList();
return new PartialViewResult
{
ViewName = "_Members",
ViewData = new ViewDataDictionary<List<ApplicationUser>>(ViewData, AppUsersList)
};
}
However the partial view doesn't get refreshed. If I put a breakpoint within this method I can see it is being hit every 5 seconds, despite Devtools stating there is an error on each attempt:
In a nut shell, I just can't seem to get my partial view to be reloaded every 5 seconds. It feels like I am close but just missing something and don't know what that is.

Answer 1

Having been reminded to check the Output window in VS a bit better, I found the cause of my problems... Well two things actually. This is the corrected method:
public async Task<IActionResult> OnGetRefreshMembers()
{
var currentUser = await _userManager.GetUserAsync(User);
AppUsersList = _userManager.Users.OrderBy(x => x.FirstName).Where(y => y.UserName != currentUser.UserName).ToList();
return new PartialViewResult
{
ViewName = "IndexPartials/_Members",
ViewData = new ViewDataDictionary<IndexModel>(ViewData, this)
};
}
Where...
I didn't include the folder that the partial lives in when naming it on the PartialViewResult
I need to return the entire IndexModel object - having updated the AppUserList property, and not just the list of AppUsers.