这只是Bruno Lopez上面建议的一个实现，但适用于Win2k +所有的WinXP服务包。我只是想把它贴出来这样别人就不用亲手卷了。(本可以作为评论发布，但我是一个新用户!)

[DllImport("kernel32", SetLastError = true, CallingConvention = CallingConvention.Winapi)]
public extern static IntPtr LoadLibrary(string libraryName);

[DllImport("kernel32", SetLastError = true, CallingConvention = CallingConvention.Winapi)]
public extern static IntPtr GetProcAddress(IntPtr hwnd, string procedureName);

private delegate bool IsWow64ProcessDelegate([In] IntPtr handle, [Out] out bool isWow64Process);

public static bool IsOS64Bit()
{
    if (IntPtr.Size == 8 || (IntPtr.Size == 4 && Is32BitProcessOn64BitProcessor()))
    {
        return true;
    }
    else
    {
        return false;
    }
}

private static IsWow64ProcessDelegate GetIsWow64ProcessDelegate()
{
  IntPtr handle = LoadLibrary("kernel32");

  if ( handle != IntPtr.Zero)
  {
    IntPtr fnPtr = GetProcAddress(handle, "IsWow64Process");

    if (fnPtr != IntPtr.Zero)
    {
      return (IsWow64ProcessDelegate)Marshal.GetDelegateForFunctionPointer((IntPtr)fnPtr, typeof(IsWow64ProcessDelegate));
    }
  }

  return null;
}

private static bool Is32BitProcessOn64BitProcessor()
{
  IsWow64ProcessDelegate fnDelegate = GetIsWow64ProcessDelegate();

  if (fnDelegate == null)
  {
    return false;
  }

  bool isWow64;
  bool retVal = fnDelegate.Invoke(Process.GetCurrentProcess().Handle, out isWow64);

  if (retVal == false)
  {
    return false;
  }

  return isWow64;
}

我发现这是检查系统平台和流程的最佳方法:

bool 64BitSystem = Environment.Is64BitOperatingSystem;
bool 64BitProcess = Environment.Is64BitProcess;

第一个属性对于64位系统返回true，对于32位系统返回false。 第二个属性对于64位进程返回true，对于32位进程返回false。

需要这两个属性是因为您可以在64位系统上运行32位进程，因此需要检查系统和进程。

在你的项目中包含以下代码:

    [DllImport("kernel32.dll", SetLastError = true, CallingConvention = CallingConvention.Winapi)]
    [return: MarshalAs(UnmanagedType.Bool)]
    private static extern bool IsWow64Process([In] IntPtr hProcess, [Out] out bool wow64Process);

    public static int GetBit()
    {
        int MethodResult = "";
        try
        {
            int Architecture = 32;

            if ((Environment.OSVersion.Version.Major == 5 && Environment.OSVersion.Version.Minor >= 1) || Environment.OSVersion.Version.Major >= 6)
            {
                using (Process p = Process.GetCurrentProcess())
                {
                    bool Is64Bit;

                    if (IsWow64Process(p.Handle, out Is64Bit))
                    {
                        if (Is64Bit)
                        {
                            Architecture = 64;

                        }

                    }

                }

            }

            MethodResult = Architecture;

        }
        catch //(Exception ex)
        {
            //ex.HandleException();
        }
        return MethodResult;
    }

像这样使用它:

string Architecture = "This is a " + GetBit() + "bit machine";

我使用:

Dim drivelet As String = Application.StartupPath.ToString
If Directory.Exists(drivelet(0) & ":\Program Files (x86)") Then
    MsgBox("64bit")
Else
    MsgBox("32bit")
End if

这将获取应用程序启动的路径，以防您将其安装在计算机上的不同位置。此外，你也可以只使用一般的C:\路径，因为99.9%的计算机都在C:\中安装了Windows。

对不起，是VB的代码。NET，但是很容易移植到c#。 它可以在Win7, x64和.Net Framework 4.8上正常工作:

Dim r As String = ""
Using searcher As ManagementObjectSearcher = New System.Management.ManagementObjectSearcher("SELECT * FROM Win32_OperatingSystem")
    Dim Information As ManagementObjectCollection = searcher.Get()
    If Information IsNot Nothing Then
        For Each obj As ManagementObject In Information
            r = obj("Caption").ToString() & _
            " - " & _
            obj("OSArchitecture").ToString() ' <--- !!! "64-bit" shown here
        Next
    End If
    MessageBox.Show(r)
End Using

还可以检查PROCESSOR_ARCHITECTURE环境变量。

它要么不存在，要么在32位Windows上被设置为“x86”。

private int GetOSArchitecture()
{
    string pa = 
        Environment.GetEnvironmentVariable("PROCESSOR_ARCHITECTURE");
    return ((String.IsNullOrEmpty(pa) || 
             String.Compare(pa, 0, "x86", 0, 3, true) == 0) ? 32 : 64);
}