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Creating a dynamic route

I am trying to create dynamic routes using ASP.Net Core and Razor Pages. Basically, I have two razor pages. One is called Pages/Home.cshtml and another is called Pages/Calendar.cshtml. Each user that logs in has their own username. So let's say I have two users in my database, Sam and Jessica and let's say Sam is logged in and goes to http://www.example.com/Sam, then it should render Pages/Home.cshtml. If Sam is logged in and goes to http://www.example.com/Sam/Calendar, then it should render Pages/Calendar.cshtml. If Jessica is logged in and she goes to http://www.example/com/Jessica, then it should render Pages/Home.cshtml.
So basically, ASP.Net Core should look at the URL and compare the username with what's in the database. If the signed in user's username matches the URL, then it should render their home page. If their username does not match the URL then it should continue down the routing pipeline. I don't need help with the database stuff or anything like that. I only need assistance on how to set up the routing.
If all this sounds confusing, then just think of Facebook. It should work exactly like Facebook. If you go to http://www.facebook.com/<your.user.name>, then it brings up your time line. If you go to http://www.facebook.com/<your.user.name>/friends, then it brings up your friends list.
I am basically trying to duplicate that same behavior that Facebook has in ASP.Net Core and Razor Pages. Can someone please provide a simple example or point me to an example? I feel like the way to do this is to use some custom middleware or a custom route attribute, but I am not sure.

You can do something like this. In the Program.cs/startup.cs modify the AddRazorPages like this.
var builder = WebApplication.CreateBuilder(args);
// Add services to the container.
builder.Services.AddRazorPages(options =>
{
options.Conventions.AddPageRoute("/Index", "{user}");
options.Conventions.AddPageRoute("/Calendar", "{user}/calendar");
});
var app = builder.Build();
Now when you access a URL like https://localhost:7131/sam/calendar you will get the calendar page. You can access the user variable like this - #RouteData.Values["user"]
And on the calendar page, you can do something like this.
public class CalendarModel : PageModel
{
public void OnGet()
{
var user = RouteData.Values["user"];
//Query the calendar information from Database.
//If empty redirect the user to the home page or something.
}
}
You can find more details about this here - Razor Pages route and app conventions in ASP.NET Core

Perform a check and redirect to a page at the start of a dot net mvc application

I have a dot net mvc application and want to perform a database check about whether the user has accepted the terms and conditions or not at the start of the application and redirect the user to the terms and condition page based on the result. Where should I place the code snippet ?
Till now I tried to redirect from global.asax file to a route and then calling a method from the control to perform the check But however it is giving the Response does not exist in the currrent context.
I tried this piece of code :
Response.RedirectToRoute("Terms",false);
I am very new to this so please excuse if the question really dumb.

Place your code snippet in the ActionResult of the Index Page(which is the default page that loads when the application starts.) in the HomeController.
Get your user from either a session and check against the user in your database to see if they have read the terms and conditions.
It will look something like this
public ActionResult Index()
{
var user = Session["loggedUser"] as User;
user = db.Users.Find(user.id);
if(!user.hasReadTerms)
{
return Redirect("/Terms");
}else
{
//continue
}
}

How do access the tab details in C# from Umbraco 7?

Please see following image.
Umbraco7 screen
I am using Umbraco 7. You can see in the image that I have 'General Messages' tab.
I have saved all error messages in that and i need to access these error messages from the code, can I do that in Csharp ?

I'm going to assume that you have a template assigned to the sign up page, and that you want to get at the messages on that View.
That being the case, you can use either:
#Umbraco.Field("yourPropertyAliasHere")
or
#Model.Content.GetPropertyValue("yourPropertyAliasHere")
The main difference is that Umbraco.Field has a bunch of useful additional parameters for things like recursive lookup.
If you want get at the properties from within some random C# in your Umbraco site that isn't related t the actual signup page, assuming you have an Umbraco Helper, you can do the following:
var page = Umbraco.TypedContent(1234); //replace '1234' with the id of your signup page!
var message = page.GetPropertyValue<string>("yourPropertyAliasHere");

Is it possible to have a single URL that points to two different pages?

I have one url (/settings) that needs to point to two different pages depending on the users security on login. One page is the existing webforms page the other is a new MVC page. Is this even possible?
Additional Info:
When the user is on either page the url needs to say website.com/settings
Solution:
Convinced the PM to change the requirements.

The short answer, yes. You can do this several ways.
Javascript
Model View Controller (Controller)
ASP.NET Web-Forms (Method)
It is often poor practice to do such an event, as it can expose data. It is indeed possible:
Javascript:
$(document).ready(function () {
if($("#Account").val() != '') {
$(".Url").attr('href', 'http://www.google.com');
}
});
Pretend #Account is a hidden field that is populated from your database. If the field is not null then modify the .Url element to navigate to link. That approach for Web-Forms is the most simple.
Web-Forms:
protected void btnAccount_Click(object sender, EventArgs e)
{
if(User.IsInRole("Account"))
Response.Redirect("~/Admin.aspx");
else
Response.Redirect("~/User.aspx");
}
That would use the default Windows Authentication for the domain, you could bend and contort to use the database to pull data. An example, the Model View Controller would be similar as the Controller will simply handle that capability.
Hope this points in right direction.

This is a redirects based approach. Create a web page mapped to /settings, and have this code run on page load.
if(User.IsAdministrator()) //I take it you have some way of determining who is an Admin, so this is just example code
{
Response.Redirect("~/AdminSettings.aspx");
}
else
{
Response.Redirect("~/UserSettings.aspx");
}
Note that you'll need security on the Admin page to make sure a regular user can't just navigate directly there.

MVC OutputCache based on Session values

Is it possible to vary the output cache in MVC based on certain values in the session? I've read a lot about using the varybycustom functionality and overriding GetVaryByCustomString in Global.asax but the session is not available at this point.
public override string GetVaryByCustomString(HttpContext context, string custom)
{
if (custom == "somekey")
//Want to check the session here (but it isn't available).
return base.GetVaryByCustomString(context, custom);
}
I understand this is because the Session isn't created until later in the request pipeline.
My concern is that without varying the cache based on the user's session, the page (which changes based on what the user has in the session, has additional HTML specific to that user etc) will get cached (as the URL is the same) and served by our load balancer, proxy servers etc. and then served to other requests with other people's session information on the page!
The reason the URL is the same is that the user comes in as a 'guest', enters some information (POST), this is validated and stored in the session and then they are re-directed back to the same page (which should now be specific to the user based on the session data).
The page itself should be cached normally because if a 'guest' visits the same URL, it should serve the same 'standard' page every time.
Is is possible to vary the caching in this way?

If you want to personalize the cache output per user, it is better you set the Location to OutputCacheLocation.Client as below. More information here
[OutputCache(Duration=3600, VaryByParam="none", Location=OutputCacheLocation.Client, NoStore=true)]
public string GetName()
{
return "Hi " + User.Identity.Name;
}

Would a Output Cache ActionFilter help at all?
Or perhaps you could refactor your view in to a layout page plus partial views for anonymous and authenticated sections, then utilize Partial Caching.

You should look into "Donut Caching", but this isn`t supported by ASP.NET MVC 3, at least not out of the box. Fortunately somebody already solved this problem for you see MvcDonutCaching
I read that ASP.NET MVC 4 will include "Donut Hole Caching" out of the box, but i cant tell if it's in the current RC or not.