How can you represent a .NET DataType in a UML Diagram

I am new to UML diagramming, but I'm 开发者_开发技巧trying to learn the ropes. Using a tool such as Visio or AgroUML how would you represent a .NET Datatype in your diagram? Two examples that I would like to do:

DataTable
List<MyObject>

The only method I see right now is creating a class that represents a datatable. As far as representing collections, I can't find any method to do that.

Thanks!

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In UML, you should use an aggregation symbol (the diamond: <>)to represent a collection of objects. A DataTable would be a class in your diagram.