WindowsPrincipal.IsInRole Method (SecurityIdentifier)
Determines whether the current principal belongs to the Windows user group with the specified security identifier (SID).
Assembly: mscorlib (in mscorlib.dll)
Return ValueType: System.Boolean
true if the current principal is a member of the specified Windows user group; otherwise, false.
The SecurityIdentifier uniquely identifies a user or group on Windows 2000, Windows Server, and Windows XP implementations. When testing for newly created role information, such as a new user or a new group, it is important to log out and log in to force the propagation of role information within the domain. Not doing so can cause the IsInRole test to return false. This method is not supported on Windows 98 or Windows Millennium Edition.
In Windows Vista, User Account Control (UAC) determines the privileges of a user. If you are a member of the Built-in Administrators group, you are assigned two run-time access tokens: a standard user access token and an administrator access token. By default, you are in the standard user role. When you attempt to perform a task that requires administrative privileges, you can dynamically elevate your role by using the Consent dialog box. The code that executes the IsInRole method does not display the Consent dialog box. The code returns false if you are in the standard user role, even if you are in the Built-in Administrators group. You can elevate your privileges before you execute the code by right-clicking the application icon and indicating that you want to run as an administrator.
For performance reasons, this is the preferable overload to determine a user's role.
The following code example demonstrates the use of the method. The BuiltinAdministratorsSid enumeration value is used to determine whether the current principal is an administrator. For the full code example, see the WindowsPrincipal.IsInRole(Int32) method.
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.