How were access rights checked?

Access rights verification is usually implemented through checking user roles and permissions within the context of the operation being performed.

In C#, a common approach is to use attributes or middleware, for example, in ASP.NET Core:

• Using attributes like [Authorize(Roles = "Admin")] to restrict access to controller methods.
• Checking permissions in code via User.IsInRole("RoleName") or verifying specific policies.

Example of access rights check in a method:

if (User.IsInRole("Admin")) {
    // Perform action accessible only to administrators
} else {
    // Deny access
}

You can also use custom authorization policies that check more complex conditions, such as belonging to a certain department or having specific permissions.

For more fine-grained control, the "Claims-based authorization" pattern is often used, where rights are stored as claims in the token or user context.