以下是XML片段的一部分,它是一个更大的XML的一部分。我一遍又一遍地尝试着获取地址行1、2、3以及城市和州、邮政编码和国家。我想将其功能化,以便根据InvoiceHeader id="XXXX"选择这些地址,但我一直遇到问题。我尝试了下面的查询或类似的内容,但我一直收到错误信息“对象引用未设置为对象的实例”。请看一下我的查询,能否指出明显的错误。
IEnumerable<string> partNos =
from item in PurchaseOrderXml.Descendants("RemitTo").Descendants("Address")
where (string)item.Attribute("id").Value == "23951768"
select (string)item;
<Invoice>
<InvoiceHeader id="23951768" status="InProcess">
<InvoiceName />
<InvoiceNumber>23951768</InvoiceNumber>
<InvoiceDate>2014-09-26 00:00:00.0</InvoiceDate>
<DueDate>2014-10-26 00:00:00.0</DueDate>
<SupplierInvoiceNo>534254504</SupplierInvoiceNo>
<InvoiceType>Invoice</InvoiceType>
<Supplier id="3825405">
<ContactInfo type="main">
<Address>
<AddressLine lineNumber="1">Post </AddressLine>
<AddressLine lineNumber="2">30 Street</AddressLine>
<AddressLine lineNumber="3">30 Street</AddressLine>
<City>Saint Louis</City>
<State>MO</State>
<PostalCode>63103-2530</PostalCode>
<Country isoCountryCode="US">United States</Country>
</Address>
</ContactInfo>
</Supplier>
<BillTo>
<Address>
<AddressLine lineNumber="1">vvvv</AddressLine>
<AddressLine lineNumber="2">vvvv</AddressLine>
<City>Philadelphia</City>
<State>PA</State>
<PostalCode>19222</PostalCode>
<Country isoCountryCode="US">United States</Country>
</Address>
</BillTo>
<RemitTo>
<Address>
<AddressLine lineNumber="1">P O BOX 535182</AddressLine>
<AddressLine lineNumber="2" />
<AddressLine lineNumber="3" />
<City>ATLANTA</City>
<State>GA</State>
<PostalCode>303535182</PostalCode>
<Country isoCountryCode="US">United States</Country>
</Address>
</RemitTo>
</InvoiceHeader>
</Invoice>