FileIOPermission.Intersect-Methode
Erstellt eine Berechtigung als Schnittmenge der aktuellen und der angegebenen Berechtigung und gibt diese zurück.
Namespace: System.Security.Permissions
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
Public Overrides Function Intersect ( _
target As IPermission _
) As IPermission
'Usage
Dim instance As FileIOPermission
Dim target As IPermission
Dim returnValue As IPermission
returnValue = instance.Intersect(target)
public override IPermission Intersect (
IPermission target
)
public:
virtual IPermission^ Intersect (
IPermission^ target
) override
public IPermission Intersect (
IPermission target
)
public override function Intersect (
target : IPermission
) : IPermission
Parameter
- target
Eine Berechtigung, deren Schnittmenge mit der aktuellen Berechtigung gebildet wird. Diese muss von demselben Typ wie die aktuelle Berechtigung sein.
Rückgabewert
Eine neue Berechtigung, die die Schnittmenge der aktuellen und der angegebenen Berechtigung darstellt. Diese neue Berechtigung ist NULL (Nothing in Visual Basic), wenn die Schnittmenge leer ist.
Ausnahmen
| Ausnahmetyp | Bedingung |
|---|---|
Der target-Parameter ist nicht NULL (Nothing in Visual Basic) und nicht von demselben Typ wie die aktuelle Berechtigung. |
Hinweise
Die Schnittmenge zweier Berechtigungen ist eine Berechtigung, die die von beiden Berechtigungen gemeinsam beschriebene Gruppe von Operationen wiedergibt. Eine Anforderung über die Schnittmenge ist nur erfolgreich, wenn sie beide ursprünglichen Berechtigungen erfolgreich durchläuft.
Beispiel
Private Function IntersectDemo() As Boolean
Dim returnValue As Boolean = True
Dim fileIO1 As String = ""
Dim fileIO2 As String = ""
Dim fileIOPerm1, fileIOPerm2, fileIOPerm3 As FileIOPermission
Dim fileIOGen1 As New FileIOGenerator()
Dim fileIOGen2 As New FileIOGenerator()
fileIOGen1.ResetIndex()
While fileIOGen1.CreateFilePath(fileIO1)
If fileIO1 = "" Then
fileIOPerm1 = New FileIOPermission(PermissionState.None)
Else
fileIOPerm1 = New FileIOPermission(FileIOPermissionAccess.Read, fileIO1)
End If
Console.WriteLine("**********************************************************" & ControlChars.Lf)
fileIOGen2.ResetIndex()
While fileIOGen2.CreateFilePath(fileIO2)
If fileIO2 = "" Then
fileIOPerm2 = New FileIOPermission(PermissionState.None)
Else
fileIOPerm2 = New FileIOPermission(FileIOPermissionAccess.Read, fileIO2)
End If
Dim firstPermission As String = IIf(fileIO1 = "" Or fileIO1 Is Nothing, "null", fileIO1)
Dim secondPermission As String = IIf(fileIO2 = "" Or fileIO2 Is Nothing, "null", fileIO2)
Try
fileIOPerm3 = CType(fileIOPerm1.Intersect(fileIOPerm2), FileIOPermission)
If Not (fileIOPerm3 Is Nothing) AndAlso Not (fileIOPerm3.GetPathList(FileIOPermissionAccess.Read) Is Nothing) Then
Console.WriteLine(("The intersection of " & firstPermission & " and " & ControlChars.Lf & ControlChars.Tab & secondPermission & " = " & ControlChars.Lf & ControlChars.Tab & CType(fileIOPerm3, FileIOPermission).GetPathList(FileIOPermissionAccess.Read)(0)))
Else
Console.WriteLine(("The intersection of " & firstPermission & " and " & secondPermission & " is null."))
End If
Catch e As Exception
Console.WriteLine(("An exception was thrown for intersection " & e.ToString()))
returnValue = False
End Try
ContinueWhile2:
End While
ContinueWhile1:
End While
Return returnValue
End Function 'IntersectDemo
private bool IntersectDemo()
{
bool returnValue = true;
string fileIO1, fileIO2;
FileIOPermission fileIOPerm1, fileIOPerm2, fileIOPerm3;
FileIOGenerator fileIOGen1 = new FileIOGenerator();
FileIOGenerator fileIOGen2 = new FileIOGenerator();
fileIOGen1.ResetIndex();
while (fileIOGen1.CreateFilePath(out fileIO1 ))
{
if (fileIO1 == "")
fileIOPerm1 = new FileIOPermission(PermissionState.None);
else
fileIOPerm1 = new FileIOPermission(FileIOPermissionAccess.Read, fileIO1);
Console.WriteLine("**********************************************************\n");
fileIOGen2.ResetIndex();
while (fileIOGen2.CreateFilePath( out fileIO2 ))
{
if (fileIO2 == "")
fileIOPerm2 = new FileIOPermission(PermissionState.None);
else
fileIOPerm2 = new FileIOPermission(FileIOPermissionAccess.Read, fileIO2);
string firstPermission = fileIO1 == "" | fileIO1 == null ? "null" : fileIO1;
string secondPermission = fileIO2 == "" | fileIO2 == null ? "null" : fileIO2;
try
{
fileIOPerm3 = (FileIOPermission)fileIOPerm1.Intersect(fileIOPerm2);
if (fileIOPerm3 != null && fileIOPerm3.GetPathList(FileIOPermissionAccess.Read) != null)
{
Console.WriteLine("The intersection of " + firstPermission + " and \n\t" + secondPermission +
" = \n\t" + ((FileIOPermission)fileIOPerm3).GetPathList(FileIOPermissionAccess.Read)[0]);
}
else
{
Console.WriteLine("The intersection of " + firstPermission + " and " + secondPermission + " is null.");
}
}
catch (Exception e)
{
Console.WriteLine("An exception was thrown for intersection " + e);
returnValue = false;
}
}
}
return returnValue;
}
bool IntersectDemo()
{
bool returnValue = true;
String^ fileIO1;
String^ fileIO2;
FileIOPermission^ fileIOPerm1;
FileIOPermission^ fileIOPerm2;
FileIOPermission^ fileIOPerm3;
FileIOGenerator^ fileIOGen1 = gcnew FileIOGenerator;
FileIOGenerator^ fileIOGen2 = gcnew FileIOGenerator;
fileIOGen1->ResetIndex();
while ( fileIOGen1->CreateFilePath ( &fileIO1 ) )
{
if (fileIO1 == "")
fileIOPerm1 = gcnew FileIOPermission(PermissionState::None);
else
fileIOPerm1 = gcnew FileIOPermission(FileIOPermissionAccess::Read, fileIO1);
Console::WriteLine( "**********************************************************\n" );
fileIOGen2->ResetIndex();
while ( fileIOGen2->CreateFilePath( &fileIO2 ) )
{
if (fileIO2 == "")
fileIOPerm2 = gcnew FileIOPermission(PermissionState::None);
else
fileIOPerm2 = gcnew FileIOPermission(FileIOPermissionAccess::Read, fileIO2);
String^ firstPermission = fileIO1 == "" || fileIO1 == nullptr ? "null" : fileIO1;
String^ secondPermission = fileIO2 == "" || fileIO2 == nullptr ? "null" : fileIO2;
try
{
fileIOPerm3 = dynamic_cast<FileIOPermission^>(fileIOPerm1->Intersect( fileIOPerm2 ));
if ( fileIOPerm3 != nullptr && fileIOPerm3->GetPathList( FileIOPermissionAccess::Read ) != nullptr )
{
Console::WriteLine( "The intersection of {0} and \n\t{1} = \n\t{2}", firstPermission, secondPermission, (dynamic_cast<FileIOPermission^>(fileIOPerm3))->GetPathList( FileIOPermissionAccess::Read )[ 0 ] );
}
else
{
Console::WriteLine( "The intersection of {0} and {1} is null.", firstPermission, secondPermission );
}
}
catch ( Exception^ e )
{
Console::WriteLine( "An exception was thrown for intersection {0}", e );
returnValue = false;
}
}
}
return returnValue;
}
// Intersect creates and returns a new permission that is
// the intersection of the current
// permission and the permission specified.
private boolean IntersectDemo()
{
boolean returnValue = true;
String fileIO1[] = new String[1];
String fileIO2[] = new String[1];
FileIOPermission fileIOPerm1[] = new FileIOPermission[1];
FileIOPermission fileIOPerm2[] = new FileIOPermission[1];
FileIOPermission fileIOPerm3;
FileIOGenerator fileIOGen1 = new FileIOGenerator();
FileIOGenerator fileIOGen2 = new FileIOGenerator();
fileIOGen1.ResetIndex();
while(fileIOGen1.CreateFilePath(fileIOPerm1, fileIO1,
FileIOPermissionAccess.Read)) {
if (fileIO1[0] == null) {
continue ;
}
Console.WriteLine("***************************"
+ "*******************************\n");
fileIOGen2.ResetIndex();
while(fileIOGen2.CreateFilePath(fileIOPerm2, fileIO2,
FileIOPermissionAccess.Read)) {
if ( fileIOPerm2[0] == null ) {
continue ;
}
String firstPermission = (fileIO1[0].equals("") ==
true | fileIO1[0] == null) ? "null" : fileIO1[0];
String secondPermission = (fileIO2[0].equals("") ==
true | fileIO2[0] == null) ? "null" : fileIO2[0];
try {
fileIOPerm3 =((FileIOPermission)(fileIOPerm1[0].
Intersect(fileIOPerm2[0])));
if (fileIOPerm3 != null &&
fileIOPerm3.GetPathList(FileIOPermissionAccess.Read)
!= null) {
Console.WriteLine(("The intersection of "
+ firstPermission + " and \n\t"
+ secondPermission + " = \n\t"
+ ((FileIOPermission)(fileIOPerm3)).
GetPathList(FileIOPermissionAccess.Read).
get_Item( 0)));
}
else {
Console.WriteLine(("The intersection of "
+ firstPermission + " and "
+ secondPermission + " is null."));
}
}
catch(System.Exception e) {
Console.WriteLine(("An exception was "
+ "thrown for intersection " + e));
returnValue = false;
}
}
}
return returnValue ;
} //IntersectDemo
Plattformen
Windows 98, Windows 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.
Versionsinformationen
.NET Framework
Unterstützt in: 2.0, 1.1, 1.0
Siehe auch
Referenz
FileIOPermission-Klasse
FileIOPermission-Member
System.Security.Permissions-Namespace