StrongNameIdentityPermission.Union(IPermission) Method

Definition

Namespace:

System.Security.Permissions

Assembly:

System.Security.Permissions.dll

Source:

StrongNameIdentityPermission.cs

Creates a permission that is the union of the current permission and the specified permission.

public:
 override System::Security::IPermission ^ Union(System::Security::IPermission ^ target);

public override System.Security.IPermission Union (System.Security.IPermission target);

override this.Union : System.Security.IPermission -> System.Security.IPermission

Public Overrides Function Union (target As IPermission) As IPermission

Parameters

target

IPermission

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

Returns

IPermission

A new permission that represents the union of the current permission and the specified permission.

Exceptions

ArgumentException

The target parameter is not null and is not of the same type as the current permission.

-or-

The two permissions are not equal and one is a subset of the other.

Examples

The following code example shows the results of the use of the Union method, not how to use the method. This example is part of a larger example provided for the StrongNameIdentityPermission class. The best use for this example is to build and execute the entire example, and view its output.

Note

The code example is intended to show the behavior of the method, not to demonstrate its use. In general, the methods of permission classes are used by the security infrastructure; they are not typically used in applications.

// Union creates a new permission that is the union of the current permission and the specified permission.
bool UnionDemo()
{
    bool returnValue = true;
    StrongNameIdentityPermission^ snIdPerm1;
    StrongNameIdentityPermission^ snIdPerm2;
    IPermission^ snIdPerm3;
    snIdPerm1 = gcnew StrongNameIdentityPermission(blob, "MyCompany.MyDepartment.*", gcnew Version("1.0.0.0"));
    snIdPerm2 = gcnew StrongNameIdentityPermission(blob, "MyCompany.MyDepartment.MyFile", gcnew Version("1.0.0.0"));
    snIdPerm3 = dynamic_cast<StrongNameIdentityPermission^>(snIdPerm1->Union( snIdPerm2 ));
    snIdPerm3 = snIdPerm1->Union( snIdPerm2 );

    try
    {
        Console::WriteLine("The union of MyCompany.MyDepartment.*" +
            "and MyCompany.MyDepartment.MyFile is " +
            (dynamic_cast<StrongNameIdentityPermission^>(snIdPerm3))->Name); 
    }
    catch (Exception^ e)
    {
        Console::WriteLine("An expected exception was thrown: " + e->Message);
    }


    return returnValue;
}

// Union creates a new permission that is the union of the current permission and the specified permission.
private bool UnionDemo()
{

    bool returnValue = true;

    StrongNameIdentityPermission snIdPerm1, snIdPerm2;
    IPermission snIdPerm3;

    snIdPerm1 = new StrongNameIdentityPermission(blob, "MyCompany.MyDepartment.*", new Version("1.0.0.0"));
    snIdPerm2 = new StrongNameIdentityPermission(blob, "MyCompany.MyDepartment.MyFile", new Version("1.0.0.0"));

    snIdPerm3 = (StrongNameIdentityPermission)snIdPerm1.Union(snIdPerm2);

    try
    {
        Console.WriteLine("The union of MyCompany.MyDepartment.*" +
        "and MyCompany.MyDepartment.MyFile is " +
        ((StrongNameIdentityPermission)snIdPerm3).Name.ToString());
    }
    catch (Exception e)
    {
        Console.WriteLine("An expected exception was thrown: " + e.Message);
    }

    return returnValue;
}

' Union creates a new permission that is the union of the current permission and the specified permission.
Private Function UnionDemo() As Boolean 
    
    Dim returnValue As Boolean = True
    
    Dim snIdPerm1, snIdPerm2 As StrongNameIdentityPermission
    Dim snIdPerm3 As IPermission
    
    snIdPerm1 = New StrongNameIdentityPermission(blob, "MyCompany.MyDepartment.*", New Version("1.0.0.0"))
    snIdPerm2 = New StrongNameIdentityPermission(blob, "MyCompany.MyDepartment.MyFile", New Version("1.0.0.0"))
    
    snIdPerm3 = CType(snIdPerm1.Union(snIdPerm2), StrongNameIdentityPermission)
    
    Try
        Console.WriteLine("The union of MyCompany.MyDepartment.*" + "and MyCompany.MyDepartment.MyFile is " + CType(snIdPerm3, StrongNameIdentityPermission).Name.ToString())
    Catch e As Exception
        Console.WriteLine("An expected exception was thrown: " + e.Message)
    End Try
    
    
    Return returnValue

End Function 'UnionDemo

Remarks

The result of a call to Union is a permission that represents all the operations represented by both the current permission and the specified permission. Any demand that passes either permission passes their union.

The union of a permission and null is the permission that is not null. The union of a permission and a subset of that permission is the permission that contains the other. Any other combination results in an ArgumentException exception being thrown.