LINQ to XML 从逗号分隔值 (CSV) 文件生成 XML 文件

参考：http://msdn.microsoft.com/zh-cn/library/bb387090.aspx

本示例演示如何使用语言集成查询 (LINQ) 和 LINQ to XML 从逗号分隔值 (CSV) 文件生成 XML 文件。

下面的代码对字符串数组执行 LINQ 查询。

在 C# 版本中，该查询使用 let 子句将每个字符串分隔成字段数组。

// Create the text file.
string csvString = @"GREAL,Great Lakes Food Market,Howard Snyder,Marketing Manager,(503) 555-7555,2732 Baker Blvd.,Eugene,OR,97403,USA
HUNGC,Hungry Coyote Import Store,Yoshi Latimer,Sales Representative,(503) 555-6874,City Center Plaza 516 Main St.,Elgin,OR,97827,USA
LAZYK,Lazy K Kountry Store,John Steel,Marketing Manager,(509) 555-7969,12 Orchestra Terrace,Walla Walla,WA,99362,USA
LETSS,Let's Stop N Shop,Jaime Yorres,Owner,(415) 555-5938,87 Polk St. Suite 5,San Francisco,CA,94117,USA";
File.WriteAllText("cust.csv", csvString);

// Read into an array of strings.
string[] source = File.ReadAllLines("cust.csv");
XElement cust = new XElement("Root",
    from str in source
    let fields = str.Split(',')
    select new XElement("Customer",
        new XAttribute("CustomerID", fields[0]),
        new XElement("CompanyName", fields[1]),
        new XElement("ContactName", fields[2]),
        new XElement("ContactTitle", fields[3]),
        new XElement("Phone", fields[4]),
        new XElement("FullAddress",
            new XElement("Address", fields[5]),
            new XElement("City", fields[6]),
            new XElement("Region", fields[7]),
            new XElement("PostalCode", fields[8]),
            new XElement("Country", fields[9])
        )
    )
);
Console.WriteLine(cust);

这段代码产生以下输出：

XML

<Root>
  <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>
  <Customer CustomerID="HUNGC">
    <CompanyName>Hungry Coyote Import Store</CompanyName>
    <ContactName>Yoshi Latimer</ContactName>
    <ContactTitle>Sales Representative</ContactTitle>
    <Phone>(503) 555-6874</Phone>
    <FullAddress>
      <Address>City Center Plaza 516 Main St.</Address>
      <City>Elgin</City>
      <Region>OR</Region>
      <PostalCode>97827</PostalCode>
      <Country>USA</Country>
    </FullAddress>
  </Customer>
  <Customer CustomerID="LAZYK">
    <CompanyName>Lazy K Kountry Store</CompanyName>
    <ContactName>John Steel</ContactName>
    <ContactTitle>Marketing Manager</ContactTitle>
    <Phone>(509) 555-7969</Phone>
    <FullAddress>
      <Address>12 Orchestra Terrace</Address>
      <City>Walla Walla</City>
      <Region>WA</Region>
      <PostalCode>99362</PostalCode>
      <Country>USA</Country>
    </FullAddress>
  </Customer>
  <Customer CustomerID="LETSS">
    <CompanyName>Let's Stop N Shop</CompanyName>
    <ContactName>Jaime Yorres</ContactName>
    <ContactTitle>Owner</ContactTitle>
    <Phone>(415) 555-5938</Phone>
    <FullAddress>
      <Address>87 Polk St. Suite 5</Address>
      <City>San Francisco</City>
      <Region>CA</Region>
      <PostalCode>94117</PostalCode>
      <Country>USA</Country>
    </FullAddress>
  </Customer>
</Root>