# Microsoft.VisualBasic.ApplicationServices

``` diff
 namespace Microsoft.VisualBasic.ApplicationServices {
+    public class ApplicationBase {
+        public ApplicationBase();
+        public CultureInfo Culture { get; }
+        public CultureInfo UICulture { get; }
+        public void ChangeCulture(string cultureName);
+        public void ChangeUICulture(string cultureName);
+        public string GetEnvironmentVariable(string name);
+    }
+    public class User {
+        public User();
+        public IPrincipal CurrentPrincipal { get; set; }
+        protected virtual IPrincipal InternalPrincipal { get; set; }
+        public bool IsAuthenticated { get; }
+        public string Name { get; }
+        public bool IsInRole(string role);
+    }
 }
```

