what is diffrence b/w Dispose and Finalize method

Finalize has some limitations toward dispose() or close().
Usually when you invoke dispose(), close() will automatically has been invoked, and viceversa .
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Garbage Collection is supposed to make programming easier, but it makes other things such as Dispose and Finalize quite complicated. You should get a book that explains them. A good book will have many pages, perhaps an enire chapter, explaining Garbage Collection, Dispose and Finalize. Dispose is usually not needed for managed objects.