PeerCollaborationPermission.IsSubsetOf(IPermission) Method

Definition

Namespace:

System.Net.PeerToPeer.Collaboration

Assembly:

System.Security.Permissions.dll

Source:

PeerCollaborationPermission.cs

Determines whether the current PeerCollaborationPermission is a subset of the specified target permission.

C#

public override bool IsSubsetOf(System.Security.IPermission target);

Parameters

target

IPermission

A permission that is to be tested for the subset relationship. This permission must be of the same type as the current permission.

Returns

Boolean

true if the current PeerCollaborationPermission is a subset of the specified permission; otherwise, false.

Exceptions

ArgumentException

The parameter is a null reference (Nothing in Visual Basic).

Remarks

The current PeerCollaborationPermission is a subset of the specified permission if the current permission specifies a set of operations that is wholly contained by the specified permission. For example, a permission that represents access to "C:\example.txt" is a subset of a permission that represents access to "C:\". If this method returns true, the current permission represents no more access to the protected resource than does the specified permission.

The following statements are required to be true for all implementations of the IsSubsetOf method. X, Y, and Z represent IPermission objects that are not a null reference (Nothing in Visual Basic).

• X.IsSubsetOf(X) returns true.

• X.IsSubsetOf(Y) returns the same value as Y.IsSubsetOf(X) if and only if X and Y represent the same set of permissions.

• If X.IsSubsetOf(Y) and Y.IsSubsetOf(Z) both return true, X.IsSubsetOf(Z) returns true.

If X represents an empty IPermission object with a permission state of None, and Y represents an IPermission object that is a null reference (Nothing in Visual Basic), X.IsSubsetOf(Y) returns true. If Z is also an empty permission, the compound set operation X.Union(Z).IsSubsetOf(Y) also returns true because the Union of two empty permissions is an empty permission.

Applies to

See also

• Intersect(IPermission)
• Union(IPermission)
• PeerCollaborationPermissionAttribute