Linq to XML：.Net Windows 窗体、XML 查询

Question

我正在尝试创建一个客户记录，其中包括名字、姓氏、SSN 和出生日期。当用户从组合框 (cboCustomer) 中选择客户时，它会调用 SelectedIndexChanged 事件。我想使用选定的索引从 XML 中获取正确的客户记录。

这是我创建的查询，但它是空的。查询下方是我的 XML 数据源。

    private void cboCustomer_SelectedIndexChanged(object sender, EventArgs e)
    {
        var doc = XElement.Load("Portfolio.xml");
        customerId = cboCustomer.SelectedIndex.ToString();
        if (cboCustomer.SelectedIndex != 0)
        {
            var custRecord =
                from account in doc.Descendants("account")
                let acct = account.Element("acct")
                where (string)account.Element("custid") == customerId
                select new
                {Fname=(string)account.Element("fname"),
                    Lname = (string)account.Element("lname"),
                    Ssn = (string)account.Element("ssn"),
                    Dob = (string)account.Element("dob")
                };
        }
    }

<?xml version="1.0" encoding="utf-8" ?>
<portfolio>
  <account>
    <acct custid="1" fname="Tommy" lname="Hawk" ssn="928-329-1929" dob="4/6/1988"></acct>
    <deposits depid="1000" depdate="1/2/2011" depamount="1350.53"></deposits>
    <deposits depid="1003" depdate="2/3/2011" depamount="1377.81"></deposits>
    <deposits depid="1008" depdate="3/14/2011" depamount="84.00"></deposits>
    <withdrawals wdid="2001" wddate="1/31/2011" wdamount="80.00"></withdrawals>
    <withdrawals wdid="2005" wddate="4/8/2011" wdamount="80.00"></withdrawals>
    <withdrawals wdid="2007" wddate="6/1/2011" wdamount="2600.00"></withdrawals>
  </account>
  <account>
    <acct custid="2" fname="I. P." lname="Nightly" ssn="457-23-4871" dob="6/1/1945"></acct>
    <deposits depid="1004" depdate="2/8/2011" depamount="741.22"></deposits>
    <deposits depid="1005" depdate="2/9/2011" depamount="47.00"></deposits>
    <deposits depid="1009" depdate="3/14/2011" depamount="89.99"></deposits>
    <withdrawals wdid="2003" wddate="3/1/2011" wdamount="55.00"></withdrawals>
    <withdrawals wdid="2004" wddate="3/3/2011" wdamount="28.00"></withdrawals>
    <withdrawals wdid="2006" wddate="4/8/2011" wdamount="450.00"></withdrawals>
  </account>
  <account>
    <acct custid="3" fname="Mary" lname="Echmass" ssn="192-01-2933" dob="8/10/1973"></acct>
    <deposits depid="1002" depdate="1/15/2011" depamount="841.77"></deposits>
    <deposits depid="1006" depdate="2/14/2011" depamount="2170.00"></deposits>
    <deposits depid="1007" depdate="3/10/2011" depamount="21.01"></deposits>
    <withdrawals wdid="2002" wddate="1/16/2011" wdamount="700.00"></withdrawals>
    <withdrawals wdid="2008" wddate="6/3/2011" wdamount="24.00"></withdrawals>
    <withdrawals wdid="2009" wddate="6/30/2100" wdamount="38.46"></withdrawals>
  </account>  
</portfolio>

Answer 1

您的 XML 中没有元素 custid，但您正在代码中查找它。

您可能想要

where acct.Attribute("custid").Value == customerId

并且需要以类似的方式修改您的 select 。