แก้ไข

แชร์ผ่าน


NetworkInformationPermission.Intersect(IPermission) Method

Definition

Creates and returns a permission that is the intersection of the current permission and the specified permission.

public:
 override System::Security::IPermission ^ Intersect(System::Security::IPermission ^ target);
public override System.Security.IPermission Intersect (System.Security.IPermission target);
override this.Intersect : System.Security.IPermission -> System.Security.IPermission
Public Overrides Function Intersect (target As IPermission) As IPermission

Parameters

target
IPermission

An IPermission to intersect with the current permission. It must be of the same type as the current permission.

Returns

A NetworkInformationPermission that represents the intersection of the current permission and the specified permission. This new permission is null if the intersection is empty or target is null.

Exceptions

Examples

The following example creates a permission object that is the intersection of existing permission objects.

System::Net::NetworkInformation::NetworkInformationPermission^ unrestricted = gcnew System::Net::NetworkInformation::NetworkInformationPermission( System::Security::Permissions::PermissionState::Unrestricted );

Console::WriteLine( L"Is unrestricted? {0}", unrestricted->IsUnrestricted() );

System::Net::NetworkInformation::NetworkInformationPermission^ read = gcnew System::Net::NetworkInformation::NetworkInformationPermission( System::Net::NetworkInformation::NetworkInformationAccess::Read );

System::Net::NetworkInformation::NetworkInformationPermission^ copyPermission = dynamic_cast<System::Net::NetworkInformation::NetworkInformationPermission^>(read->Copy());

System::Net::NetworkInformation::NetworkInformationPermission^ unionPermission = dynamic_cast<System::Net::NetworkInformation::NetworkInformationPermission^>(read->Union( unrestricted ));
Console::WriteLine( L"Is subset?{0}", read->IsSubsetOf( unionPermission ) );

System::Net::NetworkInformation::NetworkInformationPermission^ intersectPermission = dynamic_cast<System::Net::NetworkInformation::NetworkInformationPermission^>(read->Intersect( unrestricted ));
System.Net.NetworkInformation.NetworkInformationPermission unrestricted =
    new System.Net.NetworkInformation.NetworkInformationPermission(
        System.Security.Permissions.PermissionState.Unrestricted);

Console.WriteLine("Is unrestricted? " + unrestricted.IsUnrestricted());

System.Net.NetworkInformation.NetworkInformationPermission read =
    new System.Net.NetworkInformation.NetworkInformationPermission(
        System.Net.NetworkInformation.NetworkInformationAccess.Read);
System.Net.NetworkInformation.NetworkInformationPermission copyPermission =
   (System.Net.NetworkInformation.NetworkInformationPermission) read.Copy();
System.Net.NetworkInformation.NetworkInformationPermission unionPermission =
   (System.Net.NetworkInformation.NetworkInformationPermission) read.Union(unrestricted);
Console.WriteLine("Is subset?" + read.IsSubsetOf(unionPermission));
System.Net.NetworkInformation.NetworkInformationPermission intersectPermission =
   (System.Net.NetworkInformation.NetworkInformationPermission) read.Intersect(unrestricted);
Dim unrestricted As New System.Net.NetworkInformation.NetworkInformationPermission( _
    System.Security.Permissions.PermissionState.Unrestricted)
Console.WriteLine("Is unrestricted? " + unrestricted.IsUnrestricted().ToString())
Dim read As New System.Net.NetworkInformation.NetworkInformationPermission( _ 
    System.Net.NetworkInformation.NetworkInformationAccess.Read)
Dim copyPermission As System.Net.NetworkInformation.NetworkInformationPermission = _
    CType(read.Copy(), System.Net.NetworkInformation.NetworkInformationPermission)
Dim unionPermission As System.Net.NetworkInformation.NetworkInformationPermission = _
    CType(read.Union(unrestricted), System.Net.NetworkInformation.NetworkInformationPermission)
Console.WriteLine("Is subset?" + read.IsSubsetOf(unionPermission).ToString())
Dim intersectPermission As System.Net.NetworkInformation.NetworkInformationPermission = _ 
    CType(read.Intersect(unrestricted), _ 
          System.Net.NetworkInformation.NetworkInformationPermission)

Remarks

The intersection of two permissions is a permission that describes the state they both describe in common. Only a demand that passes both original permissions will pass the intersection.

Applies to