如何找出使用.NET锁定文件的进程?

时间:2008-11-25 11:34:47

标签: c# file-locking

我已经看到了关于使用HandleProcess Monitor的几个答案,但我希望能够在我自己的代码中找到(C#) 哪个进程正在锁定文件。

我有一种令人讨厌的感觉,我将不得不在win32 API中使用,但如果有人已经这样做并且可以让我走上正轨,我真的很感激帮助。

更新

与类似问题的链接

6 个答案:

答案 0 :(得分:112)

很久以前,无法可靠地获取锁定文件的进程列表,因为Windows根本没有跟踪该信息。为了支持Restart Manager API,现在可以跟踪该信息。

我将获取文件路径的代码放在一起,并返回锁定该文件的所有进程的List<Process>

using System.Runtime.InteropServices;
using System.Diagnostics;
using System;
using System.Collections.Generic;

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);

    /// <summary>
    /// Find out what process(es) have a lock on the specified file.
    /// </summary>
    /// <param name="path">Path of the file.</param>
    /// <returns>Processes locking the file</returns>
    /// <remarks>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)
    /// 
    /// </remarks>
    static public List<Process> WhoIsLocking(string path)
    {
        uint handle;
        string key = Guid.NewGuid().ToString();
        List<Process> processes = new List<Process>();

        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<Process>((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;
    }
}

使用限制权限(例如IIS)

此调用访问注册表。如果该流程无权执行此操作,您将获得ERROR_WRITE_FAULT,meaning An operation was unable to read or write to the registry。您可以有选择地将受限制帐户的权限授予注册表的必要部分。虽然让您的有限访问进程设置一个标志(例如在数据库或文件系统中,或者通过使用进程间通信机制,如队列或命名管道),然后让第二个进程调用Restart Manager API,这样更安全。

向IIS用户授予非最小权限是一种安全风险。

答案 1 :(得分:60)

从C#调用Win32非常复杂。

您应该使用http://technet.microsoft.com/en-us/sysinternals/bb896655.aspx

中的工具Handle.exe

之后,您的C#代码必须如下:

string fileName = @"c:\aaa.doc";//Path to locked file

Process tool = new Process();
tool.StartInfo.FileName = "handle.exe";
tool.StartInfo.Arguments = fileName+" /accepteula";
tool.StartInfo.UseShellExecute = false;
tool.StartInfo.RedirectStandardOutput = true;
tool.Start();           
tool.WaitForExit();
string outputTool = tool.StandardOutput.ReadToEnd();

string matchPattern = @"(?<=\s+pid:\s+)\b(\d+)\b(?=\s+)";
foreach(Match match in Regex.Matches(outputTool, matchPattern))
{
    Process.GetProcessById(int.Parse(match.Value)).Kill();
}

答案 2 :(得分:34)

handle.exe的一个好处是你可以将它作为子进程运行并解析输出。

我们在部署脚本中执行此操作 - 就像魅力一样。

答案 3 :(得分:10)

我遇到了stefan's solution的问题。下面是一个似乎运作良好的修改版本。

using System;
using System.Collections;
using System.Diagnostics;
using System.Management;
using System.IO;

static class Module1
{
    static internal ArrayList myProcessArray = new ArrayList();
    private static Process myProcess;

    public static void Main()
    {
        string strFile = "c:\\windows\\system32\\msi.dll";
        ArrayList a = getFileProcesses(strFile);
        foreach (Process p in a)
        {
            Debug.Print(p.ProcessName);
        }
    }

    private static ArrayList getFileProcesses(string strFile)
    {
        myProcessArray.Clear();
        Process[] processes = Process.GetProcesses();
        int i = 0;
        for (i = 0; i <= processes.GetUpperBound(0) - 1; i++)
        {
            myProcess = processes[i];
            //if (!myProcess.HasExited) //This will cause an "Access is denied" error
            if (myProcess.Threads.Count > 0)
            {
                try
                {
                    ProcessModuleCollection modules = myProcess.Modules;
                    int j = 0;
                    for (j = 0; j <= modules.Count - 1; j++)
                    {
                        if ((modules[j].FileName.ToLower().CompareTo(strFile.ToLower()) == 0))
                        {
                            myProcessArray.Add(myProcess);
                            break;
                            // TODO: might not be correct. Was : Exit For
                        }
                    }
                }
                catch (Exception exception)
                {
                    //MsgBox(("Error : " & exception.Message)) 
                }
            }
        }

        return myProcessArray;
    }
}

<强>更新

如果您只想知道锁定特定DLL的进程,可以执行并解析tasklist /m YourDllName.dll的输出。适用于Windows XP及更高版本。参见

What does this do? tasklist /m "mscor*"

答案 4 :(得分:7)

这适用于其他进程锁定的dll。例程不会发现文本文件被wordprocess锁定。

<强> C#:

using System.Management; 
using System.IO;   

static class Module1 
{ 
static internal ArrayList myProcessArray = new ArrayList(); 
private static Process myProcess; 

public static void Main() 
{ 

    string strFile = "c:\\windows\\system32\\msi.dll"; 
    ArrayList a = getFileProcesses(strFile); 
    foreach (Process p in a) { 
        Debug.Print(p.ProcessName); 
    } 
} 


private static ArrayList getFileProcesses(string strFile) 
{ 
    myProcessArray.Clear(); 
    Process[] processes = Process.GetProcesses; 
    int i = 0; 
    for (i = 0; i <= processes.GetUpperBound(0) - 1; i++) { 
        myProcess = processes(i); 
        if (!myProcess.HasExited) { 
            try { 
                ProcessModuleCollection modules = myProcess.Modules; 
                int j = 0; 
                for (j = 0; j <= modules.Count - 1; j++) { 
                    if ((modules.Item(j).FileName.ToLower.CompareTo(strFile.ToLower) == 0)) { 
                        myProcessArray.Add(myProcess); 
                        break; // TODO: might not be correct. Was : Exit For 
                    } 
                } 
            } 
            catch (Exception exception) { 
            } 
            //MsgBox(("Error : " & exception.Message)) 
        } 
    } 
    return myProcessArray; 
} 
} 

VB.Net:

Imports System.Management
Imports System.IO

Module Module1
Friend myProcessArray As New ArrayList
Private myProcess As Process

Sub Main()

    Dim strFile As String = "c:\windows\system32\msi.dll"
    Dim a As ArrayList = getFileProcesses(strFile)
    For Each p As Process In a
        Debug.Print(p.ProcessName)
    Next
End Sub


Private Function getFileProcesses(ByVal strFile As String) As ArrayList
    myProcessArray.Clear()
    Dim processes As Process() = Process.GetProcesses
    Dim i As Integer
    For i = 0 To processes.GetUpperBound(0) - 1
        myProcess = processes(i)
        If Not myProcess.HasExited Then
            Try
                Dim modules As ProcessModuleCollection = myProcess.Modules
                Dim j As Integer
                For j = 0 To modules.Count - 1
                    If (modules.Item(j).FileName.ToLower.CompareTo(strFile.ToLower) = 0) Then
                        myProcessArray.Add(myProcess)
                        Exit For
                    End If
                Next j
            Catch exception As Exception
                'MsgBox(("Error : " & exception.Message))
            End Try
        End If
    Next i
    Return myProcessArray
End Function
End Module

答案 5 :(得分:0)

使用linq更简单:

public void KillProcessesAssociatedToFile(string file)
    {
        GetProcessesAssociatedToFile(file).ForEach(x =>
        {
            x.Kill();
            x.WaitForExit(10000);
        });
    }

    public List<Process> GetProcessesAssociatedToFile(string file)
    {
        return Process.GetProcesses()
            .Where(x => !x.HasExited
                && x.Modules.Cast<ProcessModule>().ToList()
                    .Exists(y => y.FileName.ToLowerInvariant() == file.ToLowerInvariant())
                ).ToList();
    }