模式文档和实例文档 Schemaxmlns=http://www.w3.org/2001/xmlschena xmlns:po=http://www.examplecom/po1 targetnamespace=http://www.examplecom/pol element FormDe fault= unqualified attributeFormDefault= unqualified> Element name=purchaseOrder type= po: PurchaseOrder Type"/> Element name- comment i type=string /> <complexType name= PurchaseOrder Type> <sequence> Element name- shipTo type=po: USAddress/> <element name=billTo type=po: USAddress/> Element ref=po: comment minOccurs=O/> etc </sequence> etc </complexType> <complexType name= USAddress> <sequence> Element name=name type=string"/> Element name=street type= string </sequence> </complexType> tr </schema>模式文档和实例文档