Question

I have a xml document that has a record set like this.

<document>
  <row>
    <Pub_Code>OHB-A0011</Pub_Code>
    <Sec>16</Sec>
    <Pags>20</Pags>
    <Copies>1,000</Copies>
    <Binding>Saddle Stitch</Binding>
    <Tab>No tabs</Tab>
    <Qty>0</Qty>
    <Cover>Self Cover</Cover>
    <Tpgs>0</Tpgs>        
  </row>
</document>

I have a linq query wrtten this way:

string xml_path = @"D:\Server-Apps\BooksData.xml"; 
XElement root = XElement.Load(xml_path);

var selected = from myBooks in root.Elements("row") where myBooks.Element("Pub_Code").Value == "OHB-A0011" select myBooks;

 foreach (var d in selected)
          {
              Console.WriteLine("Pub_Code: {0}", d.Element("Pub_Code").Value);
              Console.WriteLine("Cover: {0}", d.Element("Cover").Value);
               d.SetElementValue("Tpgs", "test");

          }

I can read the value find but when I uses d.SetElementValue(“Tpgs”, “test”); nothing gets update.
the tag is already in the xml file .

Answer 1

If you want to save the updated XML back to the file, you need to do:

    root.Save(xml_path);

I added the line t the end of your program and it seems to work correctly.