I suggest you look at a sample code from [here] [1] (requires login) and try yourself first.
[http://sdllivecontent.sdl.com/LiveContent/content/en-US/SDL_Tridion_2011_SPONE/concept_95D8F90693834AF089FEBCDC0347D04D] [1]
or try this.
RepositoryItemsFilterData filterData = new RepositoryItemsFilterData(); filterData.ItemTypes = new[] { ItemType.Schema }; filterData.Recursive = true; XElement resultXml = client.GetListXml(publicationId, filterData);
And then you need to create each schema object after getting the identifiers above xml and check if it is a metadata schema.
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