WMI查询很慢，所以尽量只选择所需的成员，而不是使用Select *。

查询时间为3.4s:

foreach (var item in new System.Management.ManagementObjectSearcher("Select * from Win32_Processor").Get())

而这个需要0.122秒:

foreach (var item in new System.Management.ManagementObjectSearcher("Select NumberOfCores from Win32_Processor").Get())

Environment.ProcessorCount

(文档)

环境。ProcessorCount应该提供本地机器上的核数。

这里已经有很多答案了，但有些得到了很高的赞，有些是不正确的。

. net环境。ProcessorCount将返回不正确的值，如果您的系统WMI配置不正确，可能会严重失败。

如果你想要一个可靠的方法来计算内核，唯一的方法是Win32 API。

下面是一个c++代码片段:

#include <Windows.h>
#include <vector>

int num_physical_cores()
{
    static int num_cores = []
    {
        DWORD bytes = 0;
        GetLogicalProcessorInformation(nullptr, &bytes);
        std::vector<SYSTEM_LOGICAL_PROCESSOR_INFORMATION> coreInfo(bytes / sizeof(SYSTEM_LOGICAL_PROCESSOR_INFORMATION));
        GetLogicalProcessorInformation(coreInfo.data(), &bytes);

        int cores = 0;
        for (auto& info : coreInfo)
        {
            if (info.Relationship == RelationProcessorCore)
                ++cores;
        }
        return cores > 0 ? cores : 1;
    }();
    return num_cores;
}

由于这是一个。net c#问题，下面是移植版本:

[StructLayout(LayoutKind.Sequential)]
struct CACHE_DESCRIPTOR
{
    public byte Level;
    public byte Associativity;
    public ushort LineSize;
    public uint Size;
    public uint Type;
}

[StructLayout(LayoutKind.Explicit)]
struct SYSTEM_LOGICAL_PROCESSOR_INFORMATION_UNION
{
    [FieldOffset(0)] public byte ProcessorCore;
    [FieldOffset(0)] public uint NumaNode;
    [FieldOffset(0)] public CACHE_DESCRIPTOR Cache;
    [FieldOffset(0)] private UInt64 Reserved1;
    [FieldOffset(8)] private UInt64 Reserved2;
}

public enum LOGICAL_PROCESSOR_RELATIONSHIP
{
    RelationProcessorCore,
    RelationNumaNode,
    RelationCache,
    RelationProcessorPackage,
    RelationGroup,
    RelationAll = 0xffff
}

struct SYSTEM_LOGICAL_PROCESSOR_INFORMATION
{
    public UIntPtr ProcessorMask;
    public LOGICAL_PROCESSOR_RELATIONSHIP Relationship;
    public SYSTEM_LOGICAL_PROCESSOR_INFORMATION_UNION ProcessorInformation;
}

[DllImport("kernel32.dll")]
static extern unsafe bool GetLogicalProcessorInformation(SYSTEM_LOGICAL_PROCESSOR_INFORMATION* buffer, out int bufferSize);

static unsafe int GetProcessorCoreCount()
{
    GetLogicalProcessorInformation(null, out int bufferSize);
    int numEntries = bufferSize / sizeof(SYSTEM_LOGICAL_PROCESSOR_INFORMATION);
    var coreInfo = new SYSTEM_LOGICAL_PROCESSOR_INFORMATION[numEntries];

    fixed (SYSTEM_LOGICAL_PROCESSOR_INFORMATION* pCoreInfo = coreInfo)
    {
        GetLogicalProcessorInformation(pCoreInfo, out bufferSize);
        int cores = 0;
        for (int i = 0; i < numEntries; ++i)
        {
            ref SYSTEM_LOGICAL_PROCESSOR_INFORMATION info = ref pCoreInfo[i];
            if (info.Relationship == LOGICAL_PROCESSOR_RELATIONSHIP.RelationProcessorCore)
                ++cores;
        }
        return cores > 0 ? cores : 1;
    }
}

public static readonly int NumPhysicalCores = GetProcessorCoreCount();

我正在寻找同样的事情，但我不想安装任何nuget或服务包，所以我找到了这个解决方案，这是相当简单和直接的， 使用这个讨论，我认为运行WMIC命令并获得该值会很容易，下面是c#代码。你只需要使用系统。管理名称空间(以及用于进程等的更多标准名称空间)。

string fileName = Path.Combine(Environment.SystemDirectory, "wbem", "wmic.exe");
string arguments = @"cpu get NumberOfCores";

Process process = new Process
{
    StartInfo =
    {
        FileName = fileName,
        Arguments = arguments,
        UseShellExecute = false,
        CreateNoWindow = true,
        RedirectStandardOutput = true,
        RedirectStandardError = true
    }
};

process.Start();

StreamReader output = process.StandardOutput;
Console.WriteLine(output.ReadToEnd());


process.WaitForExit();
int exitCode = process.ExitCode;
process.Close();

一种选择是从注册中心读取数据。 MSDN文章主题:http://msdn.microsoft.com/en-us/library/microsoft.win32.registry.localmachine(v=vs.71).aspx)

处理器，我相信可以在这里，HKEY_LOCAL_MACHINE\硬件\描述\系统\中央处理器

    private void determineNumberOfProcessCores()
    {
        RegistryKey rk = Registry.LocalMachine;
        String[] subKeys = rk.OpenSubKey("HARDWARE").OpenSubKey("DESCRIPTION").OpenSubKey("System").OpenSubKey("CentralProcessor").GetSubKeyNames();

        textBox1.Text = "Total number of cores:" + subKeys.Length.ToString();
    }

我相当肯定大多数系统上都有这个注册表项。

我想把我的0.02美元投进去。