UIPermission.Union(IPermission) 方法

定义

命名空间:

System.Security.Permissions

程序集:

System.Security.Permissions.dll

程序集:

mscorlib.dll

创建一个权限，它是该权限与指定权限的并集。

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

参数

target

IPermission

与当前权限合并的权限。 它必须与当前权限属于同一类型。

返回

IPermission

表示同时兼具当前权限和指定权限的新权限。

例外

ArgumentException

target 参数不为 null，并且与当前权限不属于同一类型。

示例

下面的代码示例显示了该方法的行为 Union 。 此示例是为类提供的大型示例的 UIPermission 一部分。

备注

代码示例旨在显示方法的行为，而不是演示该方法的使用。 一般情况下，安全基础结构使用权限类的方法：它们通常不用于应用程序。

   // Union creates a new permission that is the union of the current permission
   // and the specified permission.
void UnionDemo()
{
    Console::WriteLine("\n************************  Union() Demo *************************\n");

    UIPermission ^ uiPerm1 = gcnew UIPermission(UIPermissionWindow::SafeTopLevelWindows);
    UIPermission ^ uiPerm2 = gcnew UIPermission(UIPermissionWindow::SafeSubWindows);

    UIPermission ^ p3 = dynamic_cast<UIPermission^>(uiPerm1->Union(uiPerm2));
    Console::WriteLine("   The union of {0} and  \n\t{1} = {2} ", uiPerm1->Window,
                               uiPerm2->Window, (nullptr != p3)?p3->Window.ToString():"null");
}

// Union creates a new permission that is the union of the current permission
// and the specified permission.
private static void UnionDemo()
{
    UIPermission uiPerm1 = new UIPermission(UIPermissionWindow.SafeTopLevelWindows);
    UIPermission uiPerm2 = new UIPermission(UIPermissionWindow.SafeSubWindows);
    UIPermission p3 = (UIPermission)uiPerm1.Union(uiPerm2);
    if (p3 != null)
    {
        Console.WriteLine("The union of " + uiPerm1.Window.ToString() +
            " and \n\t" + uiPerm2.Window.ToString() + " is \n\t"
            + p3.Window.ToString() + "\n");
    }
    else
    {
        Console.WriteLine("The union of " + uiPerm1.Window.ToString() +
            " and \n\t" + uiPerm2.Window.ToString() + " is null.\n");
    }
}

' Union creates a new permission that is the union of the current permission
' and the specified permission.
Private Shared Sub UnionDemo()
    Dim uiPerm1 As New UIPermission(UIPermissionWindow.SafeTopLevelWindows)
    Dim uiPerm2 As New UIPermission(UIPermissionWindow.SafeSubWindows)
    Dim p3 As UIPermission = CType(uiPerm1.Union(uiPerm2), UIPermission)
    If Not (p3 Is Nothing) Then
        Console.WriteLine("The union of " + uiPerm1.Window.ToString() + " and " + vbLf + vbTab + uiPerm2.Window.ToString() + " is " + vbLf + vbTab + p3.Window.ToString() + vbLf)

    Else
        Console.WriteLine("The union of " + uiPerm1.Window.ToString() + " and " + vbLf + vbTab + uiPerm2.Window.ToString() + " is null." + vbLf)
    End If

End Sub

注解

调用 Union 的结果是一个权限，表示由当前权限表示的所有操作，以及由指定权限表示的所有操作。 具体而言，它表示当前权限和指定权限中最宽松的值UIPermissionWindowUIPermissionClipboard和值。