与WPD文件复制到Windows Phone C＃ [英] Copy files with WPD to Windows Phone C#

问题描述

我想通过MTP至少一个文件复制到Windows手机。
我能够连接到手机和从手机复制文件到电脑下面这个教程：
的 WPD：传输内容
但是我无法拷贝文件的其他方式轮（从计算机到电话）。
这是我的代码：

I want to copy at least one file to a windows phone via MTP. I am able to connect to the phone and copy files from the phone to the computer following this tutorial: WPD: Transferring Content However I am unable to copy files the other way round (from computer to phone). This is my code:

IPortableDeviceContent content;
this._device.Content(out content);
IPortableDeviceValues values = GetRequiredPropertiesForContentType(fileName, parentObjectId);

PortableDeviceApiLib.IStream tempStream;
uint optimalTransferSizeBytes = 0;
content.CreateObjectWithPropertiesAndData(
     values,
     out tempStream,
     ref optimalTransferSizeBytes,
     null);

System.Runtime.InteropServices.ComTypes.IStream targetStream = (System.Runtime.InteropServices.ComTypes.IStream)tempStream;

try
{
    using (var sourceStream = new FileStream(fileName, FileMode.Open, FileAccess.Read))
    {
        var buffer = new byte[optimalTransferSizeBytes];
        int bytesRead;
        do
        {
            bytesRead = sourceStream.Read(buffer, 0, (int)optimalTransferSizeBytes);
            IntPtr pcbWritten = IntPtr.Zero;
            targetStream.Write(buffer, (int)optimalTransferSizeBytes, pcbWritten);
        } while (bytesRead > 0);

    }
    targetStream.Commit(0);
 }
 finally
 {
     Marshal.ReleaseComObject(tempStream);
 }

我测试了几个设备，这个代码。它适用于普通的MP3播放器，并假设本教程是正确的，所以也可以在Android手机上。
，而运行这段代码有两个不同的Windows手机，我得到以下异常：

I tested this code on several devices. It works on a normal mp3 player and assuming the tutorial is correct, it also works on an Android phone. But running this code with two different windows phone, I get following exception:

An unhandled exception of type 'System.Runtime.InteropServices.COMException' occurred in      PortableDevices.exe

Additional information: The data area passed to a system call is too small. (Exception from HRESULT: 0x8007007A)

在这行： targetStream.Write（缓冲区（INT）optimalTransferSizeBytes，pcbWritten）;

缓冲区大小为262144字节，而文件大小只有75 K字节。我希望有人有一个想法如何解决这个问题。

The buffer size is 262144 Byte, while the filesize is only 75 KByte. I hope someone has an idea how to fix this issue.

问候
j0h4nn3s

Greetings j0h4nn3s

推荐答案

我有同样的问题，原来笔者做了一个简单的错误。你写的缓冲区，而不是你一个字节你读的数字的大小。

I had the same issue, turns out the author made a simple mistake. You're writing the size of the buffer instead of the numbers you bytes you read.

替换

targetStream.Write(buffer, (int)optimalTransferSizeBytes, pcbWritten);

按

by

targetStream.Write(buffer, bytesRead, pcbWritten);

这篇关于与WPD文件复制到Windows Phone C＃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！