What is the equivant of Variant data type in C#.NET?

Question

Hi I'm using a COM object which has a method with 5 arguments 3 of them being optional (below). --------------- COM Object method objLibrary.CreateObject(ObjType ClassIdent [Option] [OptionEx1] [OptionEx2]) Parameters: ObjType - idmObjectType ClassIdent - Variant. Option - Optional. Variant. OptionEx1 - Optional. Variant. OptionEx2 - Optional. Variant. Not implemented. --------------- My code: IDMObjects.Document objDoc; objDoc = (IDMObjects.Document) (objLibrary.CreateObject(IDMObjects.idmObjectType.idmObjTypeDocument objClsDesc variant1 variant2 variant3)); ------------------- In VB and C++ I can ignore the 3 optional arguments ie. CreateObject( arg1 arg2) but in C#.NET I need to supply 5 arguments. I tried putting null empty string zero into the optional arguments (variant1 variant2 variant3) but I keep on getting Bad Variable error. I also tried declaring a variable of type Object: Object variant1 = new Object() and feed that into the optional arguments but didn't work either. Could anyone please help me? Thank you so much in advanced. Regards Tina

Alan · Answer

Munir Shaikh is correct that the Variant datatype is not used in .NET; System.Object is used instead. However when calling methods which require optional arguments from C# this usually works (I've assumed all three arguments are passed by value - precede by 'ref' otherwise): object optional = Type.Missing; objDoc = (IDMObjects.Document) (objLibrary.CreateObject(IDMObjects.idmObjectType.idmObjTypeDocument objClsDesc optional optional optional));

Munir Shaikh · Answer

Hi Just try doing Object variant1; do not create new object As per my knowledge Varient datatype is not available in vb.net.OPtion Explisit is available.I think Option Explicit is True by default which should be true in C# so instead making Dim someVariable try Object variant1; Possibly will help you. >>Munnamax