public static bool IsWin7 => Environment.OSVersion.Version.Major == 6
                       && Environment.OSVersion.Version.Minor == 1;
public static bool IsWin10 => Environment.OSVersion.Version.Major == 10;

using System;
  
namespace GetOSVersionExp
{
  class Program
  {
    static void Main(string[] args)
    {
      Version currentVersion = Environment.OSVersion.Version;
      Version compareToVersion = new Version("6.2");
      if (currentVersion.CompareTo(compareToVersion) >= 0)
      {//win8及其以上版本的系统
        Console.WriteLine("当前系统是WIN8及以上版本系统。");
      }
      else
      {
        Console.WriteLine("当前系统不是WIN8及以上版本系统。");
      }
    }
  }
}