1 根据句柄长度判断操作系统是否为64位操作系统

public static bool IsRunningOn64Bit { get { return IntPtr.Size == 8; } }

2 根据句柄长度判断操作系统是否为64位操作系统（不安全代码）

public static unsafe bool IsRunningOn64Bit { get { return (sizeof(IntPtr) == sizeof(long)); } }

将项目做如下设置：项目属性对话框->配置属性->生成->允许不安全代码块 设为"true"

3 根据AddressWidth属性判断

AddressWidth的值受CPU和操作系统的双重影响。如下：

	32bit OS	64bit OS
32bit CPU	AddressWidth = 32	N/A
64bit CPU	AddressWidth = 32	AddressWidth = 64

以下程序段读取AddressWidth的值

public static string GetAddressWidth() {     ConnectionOptions oConn = new ConnectionOptions();     System.Management.ManagementScope oMs = new System.Management.ManagementScope(" \\\\localhost", oConn);     System.Management.ObjectQuery oQuery = new System.Management.ObjectQuery("select AddressWidth from Win32_Processor");     ManagementObjectSearcher oSearcher = new ManagementObjectSearcher(oMs, oQuery);     ManagementObjectCollection oReturnCollection = oSearcher.Get();     string addressWidth = null;

    foreach (ManagementObject oReturn in oReturnCollection)     {         addressWidth = oReturn["AddressWidth"].ToString();     }

    return addressWidth; }

4 判断操作系统是否为64位操作系统

bool IsRunningOn64Bit() { #if defined(_WIN64)  return true; // 64-bit programs run only on Win64 #elif defined(_WIN32)  // 32-bit programs run on both 32-bit and 64-bit Windows  // so must sniff  bool f64 = false;  return IsWow64Process(GetCurrentProcess(), &f64) && f64; #else  return false; // Win64 does not support Win16 #endif }

网友评论：不要用IsWow64Process()，Wow64特指Windows32 On Win64。