[C#]How to check OS info

I have problems in checking OS info for installing specific application.

It use the Environment.OSVersion function to get the OS info.

Reference : 如何判斷視覺化 C#.NET 中的作業系統 Service Pack 層級
And the mentioned code below:

using System;
using System.Reflection;
using System.Runtime.InteropServices;

class Class1
{
    static void Main(string[] args)
    {
 Console.WriteLine(GetServicePack());
    }
    [StructLayout(LayoutKind.Sequential)]
    public struct OSVERSIONINFO 
    {
 public int dwOSVersionInfoSize;
 public int dwMajorVersion;
 public int dwMinorVersion;
 public int dwBuildNumber;
 public int dwPlatformId;
 [MarshalAs(UnmanagedType.ByValTStr, SizeConst=128)]
 public string szCSDVersion;
    }
    [DllImport("kernel32.Dll")] public static extern short GetVersionEx(ref OSVERSIONINFO o);
    static public  string GetServicePack()
    {
 OSVERSIONINFO os = new OSVERSIONINFO();
 os.dwOSVersionInfoSize=Marshal.SizeOf(typeof(OSVERSIONINFO)); 
 GetVersionEx(ref os);
 if (os.szCSDVersion=="")      
         return "No Service Pack Installed";
 else
        return os.szCSDVersion;
    }
}

We can get the OS version according to

//Get OS info
System.OperatingSystem osInfo = System.Environment.OSVersion; 

//Get OS platformID
System.PlatformID platformID = osInfo.Platform;

//Get OS major version
int versionMajor = osInfo.Version.Major;

//Get OS minor version
int versionMinor = osInfo.Version.Minor;

OS version info list :

OS	PlatformID	Major Version	Minor Version
Windows95	1	4	0
Windows98	1	4	10
WindowsMe	1	4	90
WindowsNT3.5	2	3	0
WindowsNT4.0	2	4	0
Windows2000	2	5	0
WindowsXP	2	5	1
Windows2003	2	5	2
WindowsVista	2	6	0
Windows7	2	6	1
Windows8

Another method :

class CheckWinVersion
    {
        public int getOSArchitecture()
        {
            string pa = Environment.GetEnvironmentVariable("PROCESSOR_ARCHITECTURE");
            return ((String.IsNullOrEmpty(pa) || String.Compare(pa, 0, "x86", 0, 3, true) == 0) ? 32 : 64);
        }
        public string getOSInfo()
        {
            //Get Operating system information.
            OperatingSystem os = Environment.OSVersion;
            //Get version information about the os.
            Version vs = os.Version;

            //Variable to hold our return value
            string operatingSystem = "";

            if (os.Platform == PlatformID.Win32Windows)
            {
                //This is a pre-NT version of Windows
                switch (vs.Minor)
                {
                    case 0:
                        operatingSystem = "95";
                        break;
                    case 10:
                        if (vs.Revision.ToString() == "2222A")
                            operatingSystem = "98SE";
                        else
                            operatingSystem = "98";
                        break;
                    case 90:
                        operatingSystem = "Me";
                        break;
                    default:
                        break;
                }
            }
            else if (os.Platform == PlatformID.Win32NT)
            {
                switch (vs.Major)
                {
                    case 3:
                        operatingSystem = "NT 3.51";
                        break;
                    case 4:
                        operatingSystem = "NT 4.0";
                        break;
                    case 5:
                        if (vs.Minor == 0)
                            operatingSystem = "2000";
                        else
                            operatingSystem = "XP";
                        break;
                    case 6:
                        if (vs.Minor == 0)
                            operatingSystem = "Vista";
                        else
                            operatingSystem = "7";
                        break;
                    default:
                        break;
                }
            }
            //Make sure we actually got something in our OS check
            //We don't want to just return " Service Pack 2" or " 32-bit"
            //That information is useless without the OS version.
            if (operatingSystem != "")
            {
                //Got something.  Let's prepend "Windows" and get more info.
                operatingSystem = "Windows " + operatingSystem;
                //See if there's a service pack installed.
                if (os.ServicePack != "")
                {
                    //Append it to the OS name.  i.e. "Windows XP Service Pack 3"
                    operatingSystem += " " + os.ServicePack;
                }
                //Append the OS architecture.  i.e. "Windows XP Service Pack 3 32-bit"
                operatingSystem += " " + getOSArchitecture().ToString() + "-bit";
            }
            //Return the information we've gathered.
            return operatingSystem;
        }
    }
}

Example:

static void Main(string[] args)
{
    CheckWinVersion ck = new CheckWinVersion();
    Console.WriteLine(ck.getOSInfo());
    Console.ReadLine();
}