我在c＃（.NET 2.0 Framework）中创建了一个复制实用程序，用于复制文件，目录和递归子目录等。该程序有一个GUI，显示当前正在复制的文件，当前文件编号（序列），要复制的文件总数以及复制操作完成的百分比。还有一个进度条，它基于当前文件/总文件。
我的问题与复制大文件有关。我一直无法找到一种方法来指示大文件的总复制进度（使用我当前使用FileInfo.CopyTo方法的类结构）。作为一种解决方法，我将文件复制操作和GUI显示分离到它们自己的线程，并设置一个视觉提示来显示正在完成的工作。至少用户知道程序没有被冻结并且仍在复制文件。
能够根据总字节数显示进度或者从FileInfo.CopyTo方法触发某种类型的事件会更好，该方法指示从当前文件复制的总字节数。
我知道FileInfo.Length属性，所以我确信MacGuyver有一种基于此的方式我自己的事件并且在GUI端有一个处理器读取更新的处理程序（可能基于检查使用某种类型的计时器的目标对象的FileInfo.Length属性？）。
有没有人知道如何做到这一点，我忽略了。如果我可以避免它，我宁愿不重写我的类来通过流复制字节并以这种方式跟踪它（虽然我想我可能会坚持走那条路）。
提前致谢
PS - 我现在一直坚持使用.NET 2.0框架，所以任何需要＆gt; = 3.0中可用功能的解决方案都不适合我。PPS - 我对任何.NET语言的解决方案都持开放态度，而不仅仅是c＃。
答案 0 :(得分：33)
FileInfo.CopyTo基本上是kernel32.dll中Win32 API调用“CopyFile”的包装器。此方法不支持进度回调。
但是，CopyFileEx方法可以，并且您可以在几分钟内编写自己的.NET包装器，如下所述： http://www.pinvoke.net/default.aspx/kernel32.CopyFileEx
答案 1 :(得分：25)
我还使用了marked answer中提供的实现。然而，我创建了一个包装器，以提供从.NET使用的更好的API。
<强>用法：
XCopy.Copy(networkFile.FullPath, temporaryFilename, true, true, (o, pce) =>
{
worker.ReportProgress(pce.ProgressPercentage, networkFile);
});
实施
/// <summary>
/// PInvoke wrapper for CopyEx
/// http://msdn.microsoft.com/en-us/library/windows/desktop/aa363852.aspx
/// </summary>
public class XCopy
{
public static void Copy(string source, string destination, bool overwrite, bool nobuffering)
{
new XCopy().CopyInternal(source, destination, overwrite, nobuffering, null);
}
public static void Copy(string source, string destination, bool overwrite, bool nobuffering, EventHandler<ProgressChangedEventArgs> handler)
{
new XCopy().CopyInternal(source, destination, overwrite, nobuffering, handler);
}
private event EventHandler Completed;
private event EventHandler<ProgressChangedEventArgs> ProgressChanged;
private int IsCancelled;
private int FilePercentCompleted;
private string Source;
private string Destination;
private XCopy()
{
IsCancelled = 0;
}
private void CopyInternal(string source, string destination, bool overwrite, bool nobuffering, EventHandler<ProgressChangedEventArgs> handler)
{
try
{
CopyFileFlags copyFileFlags = CopyFileFlags.COPY_FILE_RESTARTABLE;
if (!overwrite)
copyFileFlags |= CopyFileFlags.COPY_FILE_FAIL_IF_EXISTS;
if (nobuffering)
copyFileFlags |= CopyFileFlags.COPY_FILE_NO_BUFFERING;
Source = source;
Destination = destination;
if (handler != null)
ProgressChanged += handler;
bool result = CopyFileEx(Source, Destination, new CopyProgressRoutine(CopyProgressHandler), IntPtr.Zero, ref IsCancelled, copyFileFlags);
if (!result)
throw new Win32Exception(Marshal.GetLastWin32Error());
}
catch (Exception)
{
if (handler != null)
ProgressChanged -= handler;
throw;
}
}
private void OnProgressChanged(double percent)
{
// only raise an event when progress has changed
if ((int)percent > FilePercentCompleted)
{
FilePercentCompleted = (int)percent;
var handler = ProgressChanged;
if (handler != null)
handler(this, new ProgressChangedEventArgs((int)FilePercentCompleted, null));
}
}
private void OnCompleted()
{
var handler = Completed;
if (handler != null)
handler(this, EventArgs.Empty);
}
#region PInvoke
[DllImport("kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool CopyFileEx(string lpExistingFileName, string lpNewFileName, CopyProgressRoutine lpProgressRoutine, IntPtr lpData, ref Int32 pbCancel, CopyFileFlags dwCopyFlags);
private delegate CopyProgressResult CopyProgressRoutine(long TotalFileSize, long TotalBytesTransferred, long StreamSize, long StreamBytesTransferred, uint dwStreamNumber, CopyProgressCallbackReason dwCallbackReason,
IntPtr hSourceFile, IntPtr hDestinationFile, IntPtr lpData);
private enum CopyProgressResult : uint
{
PROGRESS_CONTINUE = 0,
PROGRESS_CANCEL = 1,
PROGRESS_STOP = 2,
PROGRESS_QUIET = 3
}
private enum CopyProgressCallbackReason : uint
{
CALLBACK_CHUNK_FINISHED = 0x00000000,
CALLBACK_STREAM_SWITCH = 0x00000001
}
[Flags]
private enum CopyFileFlags : uint
{
COPY_FILE_FAIL_IF_EXISTS = 0x00000001,
COPY_FILE_NO_BUFFERING = 0x00001000,
COPY_FILE_RESTARTABLE = 0x00000002,
COPY_FILE_OPEN_SOURCE_FOR_WRITE = 0x00000004,
COPY_FILE_ALLOW_DECRYPTED_DESTINATION = 0x00000008
}
private CopyProgressResult CopyProgressHandler(long total, long transferred, long streamSize, long streamByteTrans, uint dwStreamNumber,
CopyProgressCallbackReason reason, IntPtr hSourceFile, IntPtr hDestinationFile, IntPtr lpData)
{
if (reason == CopyProgressCallbackReason.CALLBACK_CHUNK_FINISHED)
OnProgressChanged((transferred / (double)total) * 100.0);
if (transferred >= total)
OnCompleted();
return CopyProgressResult.PROGRESS_CONTINUE;
}
#endregion
}
答案 2 :(得分：9)
我知道我参加派对有点晚了，但我为CopyFileEx制作了一个包装器，它返回Task并接受CancellationToken和IProgress<double>。不幸的是，它不能在.NET 2.0框架中工作，但对于使用4.5的任何人来说，这允许您使用await关键字。
public static class FileEx
{
public static Task CopyAsync(string sourceFileName, string destFileName)
{
return CopyAsync(sourceFileName, destFileName, CancellationToken.None);
}
public static Task CopyAsync(string sourceFileName, string destFileName, CancellationToken token)
{
return CopyAsync(sourceFileName, destFileName, token, null);
}
public static Task CopyAsync(string sourceFileName, string destFileName, IProgress<double> progress)
{
return CopyAsync(sourceFileName, destFileName, CancellationToken.None, progress);
}
public static Task CopyAsync(string sourceFileName, string destFileName, CancellationToken token, IProgress<double> progress)
{
int pbCancel = 0;
CopyProgressRoutine copyProgressHandler;
if (progress != null)
{
copyProgressHandler = (total, transferred, streamSize, streamByteTrans, dwStreamNumber, reason, hSourceFile, hDestinationFile, lpData) =>
{
progress.Report((double)transferred / total * 100);
return CopyProgressResult.PROGRESS_CONTINUE;
};
}
else
{
copyProgressHandler = EmptyCopyProgressHandler;
}
token.ThrowIfCancellationRequested();
var ctr = token.Register(() => pbCancel = 1);
var copyTask = Task.Run(() =>
{
try
{
CopyFileEx(sourceFileName, destFileName, copyProgressHandler, IntPtr.Zero, ref pbCancel, CopyFileFlags.COPY_FILE_RESTARTABLE);
token.ThrowIfCancellationRequested();
}
finally
{
ctr.Dispose();
}
}, token);
return copyTask;
}
private static CopyProgressResult EmptyCopyProgressHandler(long total, long transferred, long streamSize, long streamByteTrans, uint dwStreamNumber, CopyProgressCallbackReason reason, IntPtr hSourceFile, IntPtr hDestinationFile, IntPtr lpData)
{
return CopyProgressResult.PROGRESS_CONTINUE;
}
#region DLL Import
[DllImport("kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool CopyFileEx(string lpExistingFileName, string lpNewFileName,
CopyProgressRoutine lpProgressRoutine, IntPtr lpData, ref Int32 pbCancel,
CopyFileFlags dwCopyFlags);
delegate CopyProgressResult CopyProgressRoutine(
long totalFileSize,
long totalBytesTransferred,
long streamSize,
long streamBytesTransferred,
uint dwStreamNumber,
CopyProgressCallbackReason dwCallbackReason,
IntPtr hSourceFile,
IntPtr hDestinationFile,
IntPtr lpData);
enum CopyProgressResult : uint
{
PROGRESS_CONTINUE = 0,
PROGRESS_CANCEL = 1,
PROGRESS_STOP = 2,
PROGRESS_QUIET = 3
}
enum CopyProgressCallbackReason : uint
{
CALLBACK_CHUNK_FINISHED = 0x00000000,
CALLBACK_STREAM_SWITCH = 0x00000001
}
[Flags]
enum CopyFileFlags : uint
{
COPY_FILE_FAIL_IF_EXISTS = 0x00000001,
COPY_FILE_RESTARTABLE = 0x00000002,
COPY_FILE_OPEN_SOURCE_FOR_WRITE = 0x00000004,
COPY_FILE_ALLOW_DECRYPTED_DESTINATION = 0x00000008
}
#endregion
}
答案 3 :(得分：6)
对于上帝的爱，不要使用流来实现自己的文件副本！ Gaspar提到的Win32 CopyFile API调用能够利用例如DMA，而我敢打赌代码Will写的甜甜圈不会那么“聪明”。
CopyFileEx会对您有所帮助，或者您可以实现一个BackgroundWorker来监视目标文件不断增长的大小，并使用该信息更新进度条。后一种方法为您节省了PInvoke，但从长远来看，前者可能会更清洁。
答案 4 :(得分：5)
对于我回到Shell32的这些事情（或者是ShellUI？我不知道了）。这为您提供了一个本机Windows对话框，用户可以通过该对话框查看复制操作。我想它会替换你现有的对话框，所以它可能不是你的正确答案，但是对于那些“在紧要关头”的场景中记住它是有用的。
Microsoft.VisualBasic.FileIO.FileSystem.CopyFile(
srcPath,
dstPath,
Microsoft.VisualBasic.FileIO.UIOption.AllDialogs,
Microsoft.VisualBasic.FileIO.UICancelOption.ThrowException
);
是的，您必须引用Microsoft.VisualBasic程序集。我已经成长为love这个集会。
答案 5 :(得分：3)
感谢@Gasper和@Dennis指出CopyFileEx方法。 我用abort copy延长了dennis的答案
/// <summary>
/// Type indicates how the copy gets completed.
/// </summary>
internal enum CopyCompletedType
{
Succeeded,
Aborted,
Exception
}
/// <summary>
/// Event arguments for file copy
/// </summary>
internal class FileCopyEventArgs : EventArgs
{
/// <summary>
/// Constructor
/// </summary>
/// <param name="type">type of the copy completed type enum</param>
/// <param name="exception">exception if any</param>
public FileCopyEventArgs(CopyCompletedType type, Exception exception)
{
Type = type;
Exception = exception;
}
/// <summary>
/// Type of the copy completed type
/// </summary>
public CopyCompletedType Type
{
get;
private set;
}
/// <summary>
/// Exception if any happend during copy.
/// </summary>
public Exception Exception
{
get;
private set;
}
}
/// <summary>
/// PInvoke wrapper for CopyEx
/// http://msdn.microsoft.com/en-us/library/windows/desktop/aa363852.aspx
/// </summary>
internal class XCopy
{
private int IsCancelled;
private int FilePercentCompleted;
public XCopy()
{
IsCancelled = 0;
}
/// <summary>
/// Copies the file asynchronously
/// </summary>
/// <param name="source">the source path</param>
/// <param name="destination">the destination path</param>
/// <param name="nobuffering">Bufferig status</param>
/// <param name="handler">Event handler to do file copy.</param>
public void CopyAsync(string source, string destination, bool nobuffering)
{
try
{
//since we needed an async copy ..
Action action = new Action(
() => CopyInternal(source, destination, nobuffering)
);
Task task = new Task(action);
task.Start();
}
catch (AggregateException ex)
{
//handle the inner exception since exception thrown from task are wrapped in
//aggreate exception.
OnCompleted(CopyCompletedType.Exception, ex.InnerException);
}
catch (Exception ex)
{
OnCompleted(CopyCompletedType.Exception, ex);
}
}
/// <summary>
/// Event which will notify the subscribers if the copy gets completed
/// There are three scenarios in which completed event will be thrown when
/// 1.Copy succeeded
/// 2.Copy aborted.
/// 3.Any exception occured.
/// These information can be obtained from the Event args.
/// </summary>
public event EventHandler<FileCopyEventArgs> Completed;
/// <summary>
/// Event which will notify the subscribers if there is any progress change while copying.
/// This will indicate the progress percentage in its event args.
/// </summary>
public event EventHandler<ProgressChangedEventArgs> ProgressChanged;
/// <summary>
/// Aborts the copy asynchronously and throws Completed event when done.
/// User may not want to wait for completed event in case of Abort since
/// the event will tell that copy has been aborted.
/// </summary>
public void AbortCopyAsync()
{
Trace.WriteLine("Aborting the copy");
//setting this will cancel an operation since we pass the
//reference to copyfileex and it will periodically check for this.
//otherwise also We can check for iscancelled on onprogresschanged and return
//Progress_cancelled .
IsCancelled = 1;
Action completedEvent = new Action(() =>
{
//wait for some time because we ll not know when IsCancelled is set , at what time windows stops copying.
//so after sometime this may become valid .
Thread.Sleep(500);
//do we need to wait for some time and send completed event.
OnCompleted(CopyCompletedType.Aborted);
//reset the value , otherwise if we try to copy again since value is 1 ,
//it thinks that its aborted and wont allow to copy.
IsCancelled = 0;
});
Task completedTask = new Task(completedEvent);
completedTask.Start();
}
/// <summary>
/// Copies the file using asynchronos task
/// </summary>
/// <param name="source">the source path</param>
/// <param name="destination">the destination path</param>
/// <param name="nobuffering">Buffering status</param>
/// <param name="handler">Delegate to handle Progress changed</param>
private void CopyInternal(string source, string destination, bool nobuffering)
{
CopyFileFlags copyFileFlags = CopyFileFlags.COPY_FILE_RESTARTABLE;
if (nobuffering)
{
copyFileFlags |= CopyFileFlags.COPY_FILE_NO_BUFFERING;
}
try
{
Trace.WriteLine("File copy started with Source: " + source + " and destination: " + destination);
//call win32 api.
bool result = CopyFileEx(source, destination, new CopyProgressRoutine(CopyProgressHandler), IntPtr.Zero, ref IsCancelled, copyFileFlags);
if (!result)
{
//when ever we get the result as false it means some error occured so get the last win 32 error.
throw new Win32Exception(Marshal.GetLastWin32Error());
}
}
catch (Exception ex)
{
//the mesage will contain the requested operation was aborted when the file copy
//was cancelled. so we explicitly check for that and do a graceful exit
if (ex.Message.Contains("aborted"))
{
Trace.WriteLine("Copy aborted.");
}
else
{
OnCompleted(CopyCompletedType.Exception, ex.InnerException);
}
}
}
private void OnProgressChanged(double percent)
{
// only raise an event when progress has changed
if ((int)percent > FilePercentCompleted)
{
FilePercentCompleted = (int)percent;
var handler = ProgressChanged;
if (handler != null)
{
handler(this, new ProgressChangedEventArgs((int)FilePercentCompleted, null));
}
}
}
private void OnCompleted(CopyCompletedType type, Exception exception = null)
{
var handler = Completed;
if (handler != null)
{
handler(this, new FileCopyEventArgs(type, exception));
}
}
#region PInvoke
/// <summary>
/// Delegate which will be called by Win32 API for progress change
/// </summary>
/// <param name="total">the total size</param>
/// <param name="transferred">the transferrred size</param>
/// <param name="streamSize">size of the stream</param>
/// <param name="streamByteTrans"></param>
/// <param name="dwStreamNumber">stream number</param>
/// <param name="reason">reason for callback</param>
/// <param name="hSourceFile">the source file handle</param>
/// <param name="hDestinationFile">the destination file handle</param>
/// <param name="lpData">data passed by users</param>
/// <returns>indicating whether to continue or do somthing else.</returns>
private CopyProgressResult CopyProgressHandler(long total, long transferred, long streamSize, long streamByteTrans, uint dwStreamNumber,
CopyProgressCallbackReason reason, IntPtr hSourceFile, IntPtr hDestinationFile, IntPtr lpData)
{
//when a chunk is finished call the progress changed.
if (reason == CopyProgressCallbackReason.CALLBACK_CHUNK_FINISHED)
{
OnProgressChanged((transferred / (double)total) * 100.0);
}
//transfer completed
if (transferred >= total)
{
if (CloseHandle(hDestinationFile))
{
OnCompleted(CopyCompletedType.Succeeded, null);
}
else
{
OnCompleted(CopyCompletedType.Exception,
new System.IO.IOException("Unable to close the file handle"));
}
}
return CopyProgressResult.PROGRESS_CONTINUE;
}
[System.Runtime.InteropServices.DllImport("Kernel32")]
private extern static Boolean CloseHandle(IntPtr handle);
[DllImport("kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool CopyFileEx(string lpExistingFileName, string lpNewFileName, CopyProgressRoutine lpProgressRoutine, IntPtr lpData, ref Int32 pbCancel, CopyFileFlags dwCopyFlags);
private delegate CopyProgressResult CopyProgressRoutine(long TotalFileSize, long TotalBytesTransferred, long StreamSize, long StreamBytesTransferred, uint dwStreamNumber, CopyProgressCallbackReason dwCallbackReason,
IntPtr hSourceFile, IntPtr hDestinationFile, IntPtr lpData);
private enum CopyProgressResult : uint
{
PROGRESS_CONTINUE = 0,
PROGRESS_CANCEL = 1,
PROGRESS_STOP = 2,
PROGRESS_QUIET = 3
}
private enum CopyProgressCallbackReason : uint
{
CALLBACK_CHUNK_FINISHED = 0x00000000,
CALLBACK_STREAM_SWITCH = 0x00000001
}
[Flags]
private enum CopyFileFlags : uint
{
COPY_FILE_FAIL_IF_EXISTS = 0x00000001,
COPY_FILE_NO_BUFFERING = 0x00001000,
COPY_FILE_RESTARTABLE = 0x00000002,
COPY_FILE_OPEN_SOURCE_FOR_WRITE = 0x00000004,
COPY_FILE_ALLOW_DECRYPTED_DESTINATION = 0x00000008
}
#endregion
}
客户端可以创建XCopy类的对象并调用复制/中止方法。
答案 6 :(得分：1)