C # (. NET)에서 XML 파일을 쿼리 할 수 있는데 XSD 파일이 필요한 이유는 무엇입니까? 특정 XML 파일의 메타 데이터 파일이라는 것을 알고 있습니다. XSD에서 관계를 지정할 수 있지만 그 기능은 무엇입니까?
XML
<?xml version="1.0" encoding="utf-8" ?>
<Root>
<Customers>
<Customer CustomerID="GREAL">
<CompanyName>Great Lakes Food Market</CompanyName>
<ContactName>Howard Snyder</ContactName>
<ContactTitle>Marketing Manager</ContactTitle>
<Phone>(503) 555-7555</Phone>
<FullAddress>
<Address>2732 Baker Blvd.</Address>
<City>Eugene</City>
<Region>OR</Region>
<PostalCode>97403</PostalCode>
<Country>USA</Country>
</FullAddress>
</Customer>
</Customers>
<Orders>
<Order>
<CustomerID>GREAL</CustomerID>
<EmployeeID>6</EmployeeID>
<OrderDate>1997-05-06T00:00:00</OrderDate>
<RequiredDate>1997-05-20T00:00:00</RequiredDate>
<ShipInfo ShippedDate="1997-05-09T00:00:00">
<ShipVia>2</ShipVia>
<Freight>3.35</Freight>
<ShipName>Great Lakes Food Market</ShipName>
<ShipAddress>2732 Baker Blvd.</ShipAddress>
<ShipCity>Eugene</ShipCity>
<ShipRegion>OR</ShipRegion>
<ShipPostalCode>97403</ShipPostalCode>
<ShipCountry>USA</ShipCountry>
</ShipInfo>
</Order>
<Order>
<CustomerID>GREAL</CustomerID>
<EmployeeID>8</EmployeeID>
<OrderDate>1997-07-04T00:00:00</OrderDate>
<RequiredDate>1997-08-01T00:00:00</RequiredDate>
<ShipInfo ShippedDate="1997-07-14T00:00:00">
<ShipVia>2</ShipVia>
<Freight>4.42</Freight>
<ShipName>Great Lakes Food Market</ShipName>
<ShipAddress>2732 Baker Blvd.</ShipAddress>
<ShipCity>Eugene</ShipCity>
<ShipRegion>OR</ShipRegion>
<ShipPostalCode>97403</ShipPostalCode>
<ShipCountry>USA</ShipCountry>
</ShipInfo>
</Order>
</Orders>
</Root>
Order
제공된에 따라 요소 에서 데이터를 얻고 싶습니다 CustomerID
.
또한 : XSD에서 관계를 제공하는 목적은 무엇입니까?