using System;

using System.Linq;

using System.Collections.Generic;

using System.Xml.Linq;

public class Program

{

    public static void Main()

    {

        var doc = XDocument.Parse(XmlString);

​

        var ns = doc.Root.GetNamespaceOfPrefix("xsi");

​

        var names = doc.Descendants("Items")

            .Elements("Settings")

            .Where(x => x.Attribute(ns + "type").Value == "FileModel")

            .Select(x => x.Element("Name").Value)

            .ToList();

​

​

        names.ForEach(x => Console.WriteLine(x));

​

        var allName = string.Join(", ", names);

        Console.WriteLine("\n" + allName);

    }

        private static string XmlString = @"<?xml version=""1.0""?>

<MainClass xmlns:xsi=""http://www.w3.org/2001/XMLSchema-instance"" xmlns:xsd=""http://www.w3.org/2001/XMLSchema"">

  <Items>

    <Settings xsi:type=""FileModel"">

      <Name>Rep1</Name>

      <IsActive>true</IsActive>

      <IsHidden>false</IsHidden>

    </Settings>

    <Settings xsi:type=""FileModel"">

      <Name>Rep2</Name>

      <IsActive>true</IsActive>

      <IsHidden>false</IsHidden>

    </Settings> 

   <Settings xsi:type=""ServerModel"">

      <Name>DelRep</Name>

      <IsActive>false</IsActive>

      <IsHidden>false</IsHidden>

    </Settings>

  </Items>

</MainClass>";

​

}