Procedura: Generare XML da file CSV (LINQ to XML)

È possibile usare LINQ to XML in C# o Visual Basic per creare codice XML da un file con valori delimitati da virgole (CSV).

Esempio: generare codice XML da un file CSV

In questo esempio viene eseguita una query LINQ su una matrice di stringhe, quindi viene usata la clausola let per suddividere ogni stringa in una matrice di campi.

// 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);

' Create the text file.
Dim csvString As String = "GREAL,Great Lakes Food Market,Howard Snyder,Marketing Manager,(503) 555-7555,2732 Baker Blvd.,Eugene,OR,97403,USA" & vbCrLf & _
    "HUNGC,Hungry Coyote Import Store,Yoshi Latimer,Sales Representative,(503) 555-6874,City Center Plaza 516 Main St.,Elgin,OR,97827,USA" & vbCrLf & _
    "LAZYK,Lazy K Kountry Store,John Steel,Marketing Manager,(509) 555-7969,12 Orchestra Terrace,Walla Walla,WA,99362,USA" & vbCrLf & _
    "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.
Dim source As String() = File.ReadAllLines("cust.csv")
Dim cust As XElement = _
    <Root>
        <%= From strs In source _
            Let fields = Split(strs, ",") _
            Select _
            <Customer CustomerID=<%= fields(0) %>>
                <CompanyName><%= fields(1) %></CompanyName>
                <ContactName><%= fields(2) %></ContactName>
                <ContactTitle><%= fields(3) %></ContactTitle>
                <Phone><%= fields(4) %></Phone>
                <FullAddress>
                    <Address><%= fields(5) %></Address>
                    <City><%= fields(6) %></City>
                    <Region><%= fields(7) %></Region>
                    <PostalCode><%= fields(8) %></PostalCode>
                    <Country><%= fields(9) %></Country>
                </FullAddress>
            </Customer> _
        %>
    </Root>
Console.WriteLine(cust)

Nell'esempio viene prodotto l'output seguente:

<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>