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Marshal.IsComObject Method

Indicates whether a specified object represents a COM object.

[Visual Basic]
Public Shared Function IsComObject( _
   ByVal o As Object _
) As Boolean
public static bool IsComObject(
 object o
public: static bool IsComObject(
 Object* o
public static function IsComObject(
   o : Object
) : Boolean;


The object to check.

Return Value

true if the o parameter is a COM type; otherwise, false.


IsComObject returns true if the class type of the instance is attributed with System.Runtime.InteropServices.ComImportAttribute or if it derives directly or indirectly from a class attributed with ComImportAttribute. The Type Library Importer (Tlbimp.exe) applies this attribute for you when it imports a type library.

Two other methods also determine whether a specified object represents a COM object, but the requirements for returning true differ from this method's requirements. Type.IsImport returns true if the class (or interface) is attributed with ComImportAttribute directly; it does not return true for derived types. RegistrationServices.TypeRepresentsComType returns true if the type is attributed with ComImportAttribute or derives from a type with the same GUID.

Note   This method uses SecurityAction.LinkDemand to prevent it from being called from untrusted code; only the immediate caller is required to have SecurityPermissionAttribute.UnmanagedCode permission. If your code can be called from partially trusted code, do not pass user input to Marshal class methods without validation. For important limitations on using the LinkDemand member, see Demand vs. LinkDemand.


Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, .NET Compact Framework

.NET Framework Security: 

See Also

Marshal Class | Marshal Members | System.Runtime.InteropServices Namespace | ComImportAttribute | IsImport | TypeRepresentsComType | Type Library Importer (Tlbimp.exe)