CodeAccessPermission.Intersect(IPermission) Method

Definition

Namespace:

System.Security

Assembly:

System.Security.Permissions.dll

Source:

CodeAccessPermission.cs

When implemented by a derived class, creates and returns a permission that is the intersection of the current permission and the specified permission.

public:
 abstract System::Security::IPermission ^ Intersect(System::Security::IPermission ^ target);

public abstract System.Security.IPermission Intersect (System.Security.IPermission target);

abstract member Intersect : System.Security.IPermission -> System.Security.IPermission

Public MustOverride Function Intersect (target As IPermission) As IPermission

Parameters

target

IPermission

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

Returns

IPermission

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

Implements

Intersect(IPermission)

Exceptions

ArgumentException

The target parameter is not null and is not an instance of the same class as the current permission.

Examples

The following code example shows an override of the Intersect method. This code example is part of a larger example provided for the CodeAccessPermission class.

public:
   virtual IPermission^ Intersect( IPermission^ target ) override
   {
      Console::WriteLine( "************* Entering Intersect *********************" );
      if ( target == nullptr )
      {
         return nullptr;
      }

#if ( debug ) 
      Console::WriteLine( "This is = {0}", ((NameIdPermission)this).Name );
      Console::WriteLine( "Target is {0}", ((NameIdPermission)target).m_Name );
#endif 

      if (  !VerifyType( target ) )
      {
         throw gcnew ArgumentException( String::Format( "Argument is wrong type.", this->GetType()->FullName ) );
      }

      NameIdPermission^ operand = dynamic_cast<NameIdPermission^>(target);

      if ( operand->IsSubsetOf( this ) )
      {
         return operand->Copy();
      }
      else if ( this->IsSubsetOf( operand ) )
      {
         return this->Copy();
      }
      else
      {
         return nullptr;
      }
   }

        public override IPermission Intersect(IPermission target)
        {
            Console.WriteLine ("************* Entering Intersect *********************");
            if (target == null)
            {
                return null;
            }
#if(debug)
            Console.WriteLine ("This is = " + (( NameIdPermission)this).Name);
            Console.WriteLine ("Target is " + (( NameIdPermission)target).m_Name);
#endif
            if (!VerifyType(target))
            {
                throw new ArgumentException (String.Format ("Argument is wrong type.", this.GetType ().FullName));
            }

             NameIdPermission operand = ( NameIdPermission)target;

            if (operand.IsSubsetOf (this)) return operand.Copy ();
            else if (this.IsSubsetOf (operand)) return this.Copy ();
            else
                return null;
        }

        Public Overrides Function Intersect(ByVal target As IPermission) As IPermission
            Console.WriteLine("************* Entering Intersect *********************")
            If target Is Nothing Then
                Return Nothing
            End If
#If (Debug) Then

            Console.WriteLine(("This is = " + CType(Me, NameIdPermission).Name))
            Console.WriteLine(("Target is " + CType(target, NameIdPermission).m_name))
#End If
            If Not VerifyType(target) Then
                Throw New ArgumentException(String.Format("Argument is wrong type.", Me.GetType().FullName))
            End If

            Dim operand As NameIdPermission = CType(target, NameIdPermission)

            If operand.IsSubsetOf(Me) Then
                Return operand.Copy()
            ElseIf Me.IsSubsetOf(operand) Then
                Return Me.Copy()
            Else
                Return Nothing
            End If
        End Function 'Intersect

Remarks

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

Notes to Implementers

You must override this method in a derived class.