using System;

using System.Linq;

using System.Xml.Linq;

​

//XML: 

//<goods>

//  <good id="1">chair</good>

//  <good id="2">table</good>

//</goods>

​

var goods = new XElement("goods",

    new XElement("good", "chair", 

        new XAttribute("id", 1)),

    new XElement("good", "table", 

        new XAttribute("id", 2)));

​

//getting an element with the id = 1 attribute

//first method

var value1 = goods

    .Elements().Single(e => {

        var attr = e.Attribute("id");

        return attr != null && attr.Value == "1";

}).Value;

//value1 is "chair"

​

//second method

var value2 =

    (from e in goods.Elements()

    let attr = e.Attribute("id")

    where attr != null && attr.Value == "1"

    select e)

    .Single().Value;

//value2 is "boo"

​

Console.WriteLine(value1);

Console.WriteLine(value2);