How to check if system is 32 bit or 64 bit

Tuesday, 22 February 2011 11:53

static-bool-return-intptr-[dllimportkernel32dll

// Source: http://social.msdn.microsoft.com/Forums/en/csharpgeneral/thread/24792cdc-2d8e-454b-9c68-31a19892ca53



public static class Wow

{

  public static bool Is64BitProcess

  {

    get { return IntPtr.Size == 8; }

  }



  public static bool Is64BitOperatingSystem

  {

    get

    {

      // Clearly if this is a 64-bit process we must be on a 64-bit OS.

      if (Is64BitProcess)

        return true;

      // Ok, so we are a 32-bit process, but is the OS 64-bit?

      // If we are running under Wow64 than the OS is 64-bit.

      bool isWow64;

      return ModuleContainsFunction("kernel32.dll", "IsWow64Process") && IsWow64Process(GetCurrentProcess(), out isWow64) && isWow64;

    }

  }



  static bool ModuleContainsFunction(string moduleName, string methodName)

  {

    IntPtr hModule = GetModuleHandle(moduleName);

    if (hModule != IntPtr.Zero)

      return GetProcAddress(hModule, methodName) != IntPtr.Zero;

    return false;

  }



  [DllImport("kernel32.dll", SetLastError=true)]

  [return:MarshalAs(UnmanagedType.Bool)]

  extern static bool IsWow64Process(IntPtr hProcess, [MarshalAs(UnmanagedType.Bool)] out bool isWow64);

  [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError=true)]

  extern static IntPtr GetCurrentProcess();

  [DllImport("kernel32.dll", CharSet = CharSet.Auto)]

  extern static IntPtr GetModuleHandle(string moduleName);

  [DllImport("kernel32.dll", CharSet = CharSet.Ansi, SetLastError=true)]

  extern static IntPtr GetProcAddress(IntPtr hModule, string methodName);

}