使用 LinqToXml 循环 xml

Question

通过 xml;

对 LinqtoXml 进行试验运行

xml本身看起来像这样

<PurchaseOrders>
  <Owner ContactId="39" Owner="M Mouse" Owed="1,609.39" WeeklyDeductionRate="10.00" FromMinimumReturn="110.00" DeductionRate="0.0150" TotalDeductions="34.14" TotalToBeReturned="1,575.24">
    <Products ProductId="33" Cost="5.00" Quantity="0.40" />
    <Products ProductId="34" Cost="1.80" Quantity="0.90" />
    <Products ProductId="41" Cost="2.30" Quantity="1.30" />
    <Products ProductId="42" Cost="2.25" Quantity="1.30" />
    <Products ProductId="43" Cost="1.60" Quantity="10.50" />
    <Products ProductId="57" Cost="7.00" Quantity="13.30" />
    <Products ProductId="59" Cost="9.63" Quantity="47.00" />
    <Products ProductId="61" Cost="6.23" Quantity="32.60" />
    <Products ProductId="66" Cost="1.00" Quantity="5.60" />
    <Products ProductId="92" Cost="0.50" Quantity="4.80" />
    <Products ProductId="125" Cost="1.00" Quantity="3.80" />
    <Products ProductId="139" Cost="6.50" Quantity="3.90" />
    <Products ProductId="156" Cost="1.50" Quantity="1.70" />
    <Products ProductId="161" Cost="5.80" Quantity="44.20" />
    <Products ProductId="171" Cost="3.88" Quantity="12.00" />
    <Products ProductId="173" Cost="4.55" Quantity="32.50" />
    <Products ProductId="175" Cost="5.00" Quantity="52.90" />
    <Products ProductId="182" Cost="0.50" Quantity="18.50" />
    <Products ProductId="198" Cost="0.50" Quantity="27.40" />
    <Products ProductId="220" Cost="1.50" Quantity="38.60" />
    <Products ProductId="231" Cost="6.00" Quantity="0.90" />
    <Products ProductId="236" Cost="0.85" Quantity="2.10" />
  </Owner>
  <Owner ContactId="42" Owner="F Flintstone" Owed="710.01" WeeklyDeductionRate="10.00" FromMinimumReturn="110.00" DeductionRate="0.0150" TotalDeductions="20.65" TotalToBeReturned="689.35">
    <Products ProductId="32" Cost="6.00" Quantity="0.50" />
    <Products ProductId="33" Cost="5.00" Quantity="2.00" />
    <Products ProductId="34" Cost="1.80" Quantity="7.80" />
    <Products ProductId="57" Cost="7.00" Quantity="3.10" />
    <Products ProductId="59" Cost="10.00" Quantity="16.30" />
    <Products ProductId="61" Cost="6.60" Quantity="13.90" />
    <Products ProductId="131" Cost="0.90" Quantity="1.70" />
    <Products ProductId="156" Cost="1.50" Quantity="1.50" />
    <Products ProductId="161" Cost="5.80" Quantity="17.40" />
    <Products ProductId="164" Cost="1.10" Quantity="3.10" />
    <Products ProductId="171" Cost="3.80" Quantity="5.70" />

我有以下适合时尚的代码：

 Dim SupplierId As Integer
        Dim lSubTotal As Decimal
        Dim lDeductions As Decimal
        Dim lToBeReturned As Decimal

        Dim lProductId As Integer
        Dim xElem = XElement.Load(GenerateStreamFromString(SubmissionsEditor.Text))
        ' Dim node As XElement

        Dim owners = From owner In xElem.Descendants("Owner")
                     Select owner

        For Each owner In owners
            SupplierId = CInt(owner.Attribute("ContactId").Value)
            lSubTotal = CDec(owner.Attribute("Owed").Value)
            lDeductions = CDec(owner.Attribute("TotalDeductions").Value)
            lToBeReturned = CDec(owner.Attribute("TotalToBeReturned").Value)
            SiAuto.Main.LogInt(NameOf(SupplierId), SupplierId)
            SiAuto.Main.LogDecimal(NameOf(lSubTotal), lSubTotal)
            SiAuto.Main.LogDecimal(NameOf(lDeductions), lDeductions)
            SiAuto.Main.LogDecimal(NameOf(lToBeReturned), lToBeReturned)

            SiAuto.Main.LogMessage("Process Purchase Order Header Here")

            Dim details = From detail In xElem.Descendants("Products")
                          Where CInt(owner.Attribute("ContactId").Value) = SupplierId
                          Select detail

            For Each detail In details
                lProductId = CInt(detail.Attribute("ProductId").Value)
                SiAuto.Main.LogInt(NameOf(lProductId), lProductId)
            Next
        Next

当我检查日志时，很明显每个所有者元素都在处理，但不是只记录每个所有者元素的 ProductId，然后继续处理下一个所有者，而是记录每个所有者的所有 productId .

我怀疑是这一点出了问题

Dim details = From detail In xElem.Descendants("Products")
                          Where CInt(owner.Attribute("ContactId").Value) = SupplierId
                          Select detail

但是是xElem后面的位还是where条件？

谢谢

Answer 1

Descendants 方法 returns 所有子节点的所有 Products 方法，如文档所述 here, on MSDN。这将包括孙子。

如果您想包括特定的产品节点，请优化您的搜索：

Dim details = From detail In owner.Descendants("Products")
              Where CInt(owner.Attribute("ContactId").Value) = SupplierId
              Select detail

请注意，我选择的是 owner.Descendants，而不是 xElem.Descendants。

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