其他答案依赖于旧信息。这个提供了更好的解决方案。

很久以前，在Windows中可靠地获取锁定文件的进程列表是不可能的，因为Windows根本没有跟踪这些信息。为了支持Restart Manager API，现在跟踪这些信息。 Restart Manager API从Windows Vista和Windows Server 2008开始提供支持(Restart Manager：运行时要求)。

我编写了代码，输入一个文件路径，返回锁定该文件的所有进程的List。

static public class FileUtil
{
    [StructLayout(LayoutKind.Sequential)]
    struct RM_UNIQUE_PROCESS
    {
        public int dwProcessId;
        public System.Runtime.InteropServices.ComTypes.FILETIME ProcessStartTime;
    }
    const int RmRebootReasonNone = 0;
    const int CCH_RM_MAX_APP_NAME = 255;
    const int CCH_RM_MAX_SVC_NAME = 63;
    enum RM_APP_TYPE
    {
        RmUnknownApp = 0,
        RmMainWindow = 1,
        RmOtherWindow = 2,
        RmService = 3,
        RmExplorer = 4,
        RmConsole = 5,
        RmCritical = 1000
    }
    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
    struct RM_PROCESS_INFO
    {
        public RM_UNIQUE_PROCESS Process;
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = CCH_RM_MAX_APP_NAME + 1)]
        public string strAppName;
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = CCH_RM_MAX_SVC_NAME + 1)]
        public string strServiceShortName;
        public RM_APP_TYPE ApplicationType;
        public uint AppStatus;
        public uint TSSessionId;
        [MarshalAs(UnmanagedType.Bool)]
        public bool bRestartable;
    }
    [DllImport("rstrtmgr.dll", CharSet = CharSet.Unicode)]
    static extern int RmRegisterResources(uint pSessionHandle,
                                          UInt32 nFiles,
                                          string[] rgsFilenames,
                                          UInt32 nApplications,
                                          [In] RM_UNIQUE_PROCESS[] rgApplications,
                                          UInt32 nServices,
                                          string[] rgsServiceNames);
    [DllImport("rstrtmgr.dll", CharSet = CharSet.Auto)]
    static extern int RmStartSession(out uint pSessionHandle, int dwSessionFlags, string strSessionKey);
    [DllImport("rstrtmgr.dll")]
    static extern int RmEndSession(uint pSessionHandle);
    [DllImport("rstrtmgr.dll")]
    static extern int RmGetList(uint dwSessionHandle,
                                out uint pnProcInfoNeeded,
                                ref uint pnProcInfo,
                                [In, Out] RM_PROCESS_INFO[] rgAffectedApps,
                                ref uint lpdwRebootReasons);
    /// 

    /// Find out what process(es) have a lock on the specified file.
    /// 
    /// Path of the file.
    /// Processes locking the file
    /// See also:
    /// http://msdn.microsoft.com/en-us/library/windows/desktop/aa373661(v=vs.85).aspx
    /// http://wyupdate.googlecode.com/svn-history/r401/trunk/frmFilesInUse.cs (no copyright in code at time of viewing)
    /// 
    /// 
    static public List WhoIsLocking(string path)
    {
        uint handle;
        string key = Guid.NewGuid().ToString();
        List processes = new List();
        int res = RmStartSession(out handle, 0, key);
        if (res != 0)
            throw new Exception("Could not begin restart session.  Unable to determine file locker.");
        try
        {
            const int ERROR_MORE_DATA = 234;
            uint pnProcInfoNeeded = 0,
                 pnProcInfo = 0,
                 lpdwRebootReasons = RmRebootReasonNone;
            string[] resources = new string[] { path }; // Just checking on one resource.
            res = RmRegisterResources(handle, (uint)resources.Length, resources, 0, null, 0, null);
            if (res != 0) 
                throw new Exception("Could not register resource.");                                    
            //Note: there's a race condition here -- the first call to RmGetList() returns
            //      the total number of process. However, when we call RmGetList() again to get
            //      the actual processes this number may have increased.
            res = RmGetList(handle, out pnProcInfoNeeded, ref pnProcInfo, null, ref lpdwRebootReasons);
            if (res == ERROR_MORE_DATA)
            {
                // Create an array to store the process results
                RM_PROCESS_INFO[] processInfo = new RM_PROCESS_INFO[pnProcInfoNeeded];
                pnProcInfo = pnProcInfoNeeded;
                // Get the list
                res = RmGetList(handle, out pnProcInfoNeeded, ref pnProcInfo, processInfo, ref lpdwRebootReasons);
                if (res == 0)
                {
                    processes = new List((int)pnProcInfo);
                    // Enumerate all of the results and add them to the 
                    // list to be returned
                    for (int i = 0; i < pnProcInfo; i++)
                    {
                        try
                        {
                            processes.Add(Process.GetProcessById(processInfo[i].Process.dwProcessId));
                        }
                        // catch the error -- in case the process is no longer running
                        catch (ArgumentException) { }
                    }
                }
                else
                    throw new Exception("Could not list processes locking resource.");                    
            }
            else if (res != 0)
                throw new Exception("Could not list processes locking resource. Failed to get size of result.");                    
        }
        finally
        {
            RmEndSession(handle);
        }
        return processes;
    }
}

更新

这里还有另一个讨论和示例代码，介绍如何使用Restart Manager API。

当我面临类似的问题时，我使用了以下代码：

public class FileManager
{
    private string _fileName;
    private int _numberOfTries;
    private int _timeIntervalBetweenTries;
    private FileStream GetStream(FileAccess fileAccess)
    {
        var tries = 0;
        while (true)
        {
            try
            {
                return File.Open(_fileName, FileMode.Open, fileAccess, Fileshare.None); 
            }
            catch (IOException e)
            {
                if (!IsFileLocked(e))
                    throw;
                if (++tries > _numberOfTries)
                    throw new MyCustomException("The file is locked too long: " + e.Message, e);
                Thread.Sleep(_timeIntervalBetweenTries);
            }
        }
    }
    private static bool IsFileLocked(IOException exception)
    {
        int errorCode = Marshal.GetHRForException(exception) & ((1 << 16) - 1);
        return errorCode == 32 || errorCode == 33;
    }
    // other code
}