In ASP.NET Core 3.0 with endpoint routing enabled, you can get a route parameter value like this:
public class MyRequirementHandler : AuthorizationHandler<MyRequirement>
{
private readonly IHttpContextAccessor _httpContextAccessor;
public MyRequirementHandler(IHttpContextAccessor httpContextAccessor)
{
_httpContextAccessor = httpContextAccessor ?? throw new ArgumentNullException(nameof(httpContextAccessor));
}
protected override async Task HandleRequirementAsync(AuthorizationHandlerContext context, MyRequirement requirement)
{
var routeData = _httpContextAccessor.HttpContext.GetRouteData();
var areaName = routeData?.Values["area"]?.ToString();
var area = string.IsNullOrWhiteSpace(areaName) ? string.Empty : areaName;
var controllerName = routeData?.Values["controller"]?.ToString();
var controller = string.IsNullOrWhiteSpace(controllerName) ? string.Empty : controllerName;
var actionName = routeData?.Values["action"]?.ToString();
var action = string.IsNullOrWhiteSpace(actionName) ? string.Empty : actionName;
//...
}
}