删除的zip文件导致e.Data.GetData（“FileContents”）抛出异常 [英] Dropped zip file causes e.Data.GetData("FileContents") to throw an exception
问题描述
我试图在WPF应用程序中实现一个处理程序，用于从压缩文件夹拖动的文件。处理程序应该获取文件内容进行进一步处理。
I'm trying to implement a handler in my WPF application for files dragged from a zip archive. The handler should get the file content for further processing.
我的环境：安装了Windows 7，7-zip，Visual Studio 2012 Express，.Net 4.5
My environment: Windows7, 7-zip installed, Visual Studio 2012 Express, .Net 4.5
这是一个简单的MainWindow应用程序的代码，用于演示问题：
Here is the code of a simple MainWindow app to demonstrate the problem:
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
AllowDrop= true;
Drop += onDrop;
}
private void onDrop(object sender, DragEventArgs e)
{
if (e.Data.GetDataPresent("FileContents"))
{
var fileContents = e.Data.GetData("FileContents");
//get file contents...
}
}
}
当我将包含在zip存档中的文件拖动到我的窗口时，对e.Data.GetData（FileContents）的调用会使用以下callstack引发一个System.ArgumentException（Argument out of Range）：
When I drag a file contained in a zip archive to my Window the call to e.Data.GetData("FileContents") throws a System.ArgumentException ("Argument out of Range") with the following callstack:
System.Windows.DataObject.OleConverter.GetDataInner(formatetc, medium)
System.Windows.DataObject.OleConverter.GetDataFromOleHGLOBAL(format, aspect, index)
System.Windows.DataObject.OleConverter.GetDataFromBoundOleDataObject(format, aspect, index)
System.Windows.DataObject.OleConverter.GetData(format, autoConvert, aspect, index)
System.Windows.DataObject.OleConverter.GetData(format, autoConvert)
System.Windows.DataObject.GetData(format, autoConvert)
System.Windows.DataObject.GetData(format)
TestZip.MainWindow.onDrop(sender, e) Zeile 34 C#
我查了这个OleConverter的源代码（<啊REF =http://reflector.webtropy.com/default.aspx/Dotnetfx_Win7_3@5@1/Dotnetfx_Win7_3@5@1/3@5@1/DEVDIV/depot/DevDiv/releases/Orcas/NetFXw7/wpf/src / Core / CSharp / System / Windows / dataobject @ cs / 1 / dataobject @ csrel =nofollow> http://reflector.webtropy.com/default.aspx/Dotnetfx_Win7_3@5@1/Dotnetfx_Win7_3@5@1 / 3 @ 5 @ 1 / DEVDIV / depot / DevDiv / releases / Orcas / NetFXw7 / wpf / src / Core / CSharp / System / Windows / dataobject @ cs / 1 / dataobject @ cs ），但GetDataInner方法实现像
I've looked up the source code of this OleConverter (http://reflector.webtropy.com/default.aspx/Dotnetfx_Win7_3@5@1/Dotnetfx_Win7_3@5@1/3@5@1/DEVDIV/depot/DevDiv/releases/Orcas/NetFXw7/wpf/src/Core/CSharp/System/Windows/dataobject@cs/1/dataobject@cs) but the GetDataInner() method is implemented like
private void GetDataInner(ref FORMATETC formatetc, out STGMEDIUM medium)
{
new SecurityPermission(SecurityPermissionFlag.UnmanagedCode).Assert(); // BlessedAssert
try
{
_innerData.GetData(ref formatetc, out medium);
}
finally
{
SecurityPermission.RevertAssert();
}
}
所以这还没有提供进一步的错误信息
So this does also not provide further info of what's wrong here.
我还尝试使用卸载的7-zip和不同的zip存档，但没有变化。
I also tried with uninstalled 7-zip and with different zip archives, but no change.
我的问题：有没有人知道这里有什么问题？我需要做什么才能将压缩文件中的文件的内容放到我的窗口上？
My question: Does any one have a clue what's going wrong here? What do I need to do in order to get the content of a file from a zip-archive dropped onto my window?
推荐答案
老问题，但我今天需要这样做....
Old question but I needed to do this today so....
首先你需要得到FileDescriptor的内容，这里是一个读它们的类。
First you need to get the "FileDescriptor" contents, here's a class which reads them.
/// <summary>
/// Specifies which fields are valid in a FileDescriptor Structure
/// </summary>
[Flags]
enum FileDescriptorFlags : uint
{
ClsId = 0x00000001,
SizePoint = 0x00000002,
Attributes = 0x00000004,
CreateTime = 0x00000008,
AccessTime = 0x00000010,
WritesTime = 0x00000020,
FileSize = 0x00000040,
ProgressUI = 0x00004000,
LinkUI = 0x00008000,
Unicode = 0x80000000,
}
internal static class FileDescriptorReader
{
internal sealed class FileDescriptor
{
public FileDescriptorFlags Flags{get;set;}
public Guid ClassId{get;set;}
public Size Size{get;set;}
public Point Point{get;set;}
public FileAttributes FileAttributes{get;set;}
public DateTime CreationTime{get;set;}
public DateTime LastAccessTime{get;set;}
public DateTime LastWriteTime{get;set;}
public Int64 FileSize{get;set;}
public string FileName{get;set;}
public FileDescriptor(BinaryReader reader)
{
//Flags
Flags = (FileDescriptorFlags)reader.ReadUInt32();
//ClassID
ClassId = new Guid(reader.ReadBytes(16));
//Size
Size = new Size(reader.ReadInt32(), reader.ReadInt32());
//Point
Point = new Point(reader.ReadInt32(), reader.ReadInt32());
//FileAttributes
FileAttributes = (FileAttributes)reader.ReadUInt32();
//CreationTime
CreationTime = new DateTime(1601,1,1).AddTicks(reader.ReadInt64());
//LastAccessTime
LastAccessTime = new DateTime(1601,1,1).AddTicks(reader.ReadInt64());
//LastWriteTime
LastWriteTime = new DateTime(1601, 1, 1).AddTicks(reader.ReadInt64());
//FileSize
FileSize = reader.ReadInt64();
//FileName
byte[] nameBytes = reader.ReadBytes(520);
int i = 0;
while(i < nameBytes.Length)
{
if (nameBytes[i] == 0 && nameBytes[i + 1] == 0)
break;
i++;
i++;
}
FileName = UnicodeEncoding.Unicode.GetString(nameBytes, 0, i);
}
}
public static IEnumerable<FileDescriptor> Read(Stream fileDescriptorStream)
{
BinaryReader reader = new BinaryReader(fileDescriptorStream);
var count = reader.ReadUInt32();
while (count > 0)
{
FileDescriptor descriptor = new FileDescriptor(reader);
yield return descriptor;
count--;
}
}
public static IEnumerable<string> ReadFileNames(Stream fileDescriptorStream)
{
BinaryReader reader = new BinaryReader(fileDescriptorStream);
var count = reader.ReadUInt32();
while(count > 0)
{
FileDescriptor descriptor = new FileDescriptor(reader);
yield return descriptor.FileName;
count--;
}
}
}
现在使用它可以获得每个文件的匹配文件内容：
Now using that you can get the matching file content for each file:
static class ClipboardHelper
{
internal static MemoryStream GetFileContents(Windows.IDataObject dataObject, int index)
{
//cast the default IDataObject to a com IDataObject
IDataObject comDataObject;
comDataObject = (IDataObject)dataObject;
Windows.DataFormat Format = Windows.DataFormats.GetDataFormat("FileContents");
if (Format == null)
return null;
FORMATETC formatetc = new FORMATETC();
formatetc.cfFormat = (short)Format.Id;
formatetc.dwAspect = DVASPECT.DVASPECT_CONTENT;
formatetc.lindex = index;
formatetc.tymed = TYMED.TYMED_ISTREAM | TYMED.TYMED_HGLOBAL;
//create STGMEDIUM to output request results into
STGMEDIUM medium = new STGMEDIUM();
//using the com IDataObject interface get the data using the defined FORMATETC
comDataObject.GetData(ref formatetc, out medium);
switch (medium.tymed)
{
case TYMED.TYMED_ISTREAM: return GetIStream(medium);
default: throw new NotSupportedException();
}
}
private static MemoryStream GetIStream(STGMEDIUM medium)
{
//marshal the returned pointer to a IStream object
IStream iStream = (IStream)Marshal.GetObjectForIUnknown(medium.unionmember);
Marshal.Release(medium.unionmember);
//get the STATSTG of the IStream to determine how many bytes are in it
var iStreamStat = new System.Runtime.InteropServices.ComTypes.STATSTG();
iStream.Stat(out iStreamStat, 0);
int iStreamSize = (int)iStreamStat.cbSize;
//read the data from the IStream into a managed byte array
byte[] iStreamContent = new byte[iStreamSize];
iStream.Read(iStreamContent, iStreamContent.Length, IntPtr.Zero);
//wrapped the managed byte array into a memory stream
return new MemoryStream(iStreamContent);
}
}
现在您可以枚举文件内容中的流：
Now you can enumerate the streams in the file contents:
var fileDescriptor = (MemoryStream)Clipboard.GetDataObject().GetData("FileGroupDescriptorW");
var files = FileDescriptorReader.Read(fileDescriptor)
foreach (var fileContentFile in files)
{
if ((fileContentFile.FileAttributes & FileAttributes.Directory) != 0)
{
//Do something with directories?
//Note that directories do not have FileContents
//And will throw if we try to read them
}
else
{
var fileData = ClipboardHelper.GetFileContents(Clipboard.GetDataObject(), i);
fileData.Position = 0;
//Do something with the fileContent Stream
}
i++;
}
这篇关于删除的zip文件导致e.Data.GetData（“FileContents”）抛出异常的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
