HTTP协议下用Web Service上传大文件的解决方案

用HTTP协议上传大文件也许是个不好办的问题。主要是它的不连续性，使得上传文件感觉很“危险”。特别是很大的文件(几百MB甚至是上G的文件)，心里总觉得不踏实，一不小心就会出现问题，而一但出现问题就无法继续上传，这是很郁闷的。

后来在一些网站上找到一些上传文件的组件，但都是要用到一些COM组件。至于后来的ASP.net下上传大文件的解决方案，我也做过一个组件，后来发现根本就不用自己写什么组件，利用ASP.net自己的上传方法也可以解决大文件上传，真是郁闷的要死了。。。。

回想之后，决定用Web service来做一个文件上传，还是利用HTTP协议，这样不用在服务器上做太多的变动，而客户端也简单。

首先是解决方案的设计：因为Web service可以利用SOAP来传递数据，而且可以传递十进制数据，因此可以想到，在服务上公开一个方法，参数可以是byte数组，这样可以把文件分块的上传到服务器。这一解决方法我做过，但速度很慢。后来在MS上找到一些文章，用MS最新公开的服务组件上传文件，速度快了很多。而自己所要做的就是组织一些安全性的问题。

部份代码： Upload Instance

引用内容

using System;
using System.IO;
using Microsoft.Web.Services2;
using Microsoft.Web.Services2.Dime;

namespace Webb.WAVE.WinUpload
{
/**//// <summary>
/// Summary description for Controls.
/// </summary>
public class UploadInstance2
{
Fields#region Fields
private string m_GUID;
private DateTime m_uploadTime;
private long m_fileLength;
private long m_currentPoint;
private string m_pathOnserver;
private long m_userID;
#endregion

Properties#region Properties
public long UserID
{
get{return this.m_userID;}
set{this.m_userID=value;}
}
public string GUID
{
get{return this.m_GUID;}
set{this.m_GUID=value;}
}
public DateTime UploadTime
{
get{return this.m_uploadTime;}
set{}
}
public long FileLength
{
get{return this.m_fileLength;}
set{this.m_fileLength=value;}
}
public long CurrentPoing
{
get{return this.m_currentPoint;}
set{this.m_currentPoint=value;}
}
public string PathOnServer
{
get{return this.m_pathOnserver;}
set{this.m_pathOnserver=value;}
}
public string FullPathOnServer
{
get
{
if(this.m_GUID!=string.Empty&&this.m_pathOnserver!=string.Empty)
{
return Path.Combine(this.m_pathOnserver,this.m_GUID+".rem");
}
else
{
return string.Empty;
}
}
}
public string FileName
{
get
{
if(this.m_GUID!=string.Empty)
{
return this.m_GUID+".rem";
}
else
{
return string.Empty;
}
}
}

#endregion

public UploadInstance2()
{
this.m_GUID = System.Guid.NewGuid().ToString();
this.m_uploadTime = System.DateTime.Now;
this.m_currentPoint = 0;
this.m_fileLength = 0;
this.m_pathOnserver = string.Empty;
}
public UploadInstance2(string i_path,string i_GUID,long i_fileLength)
{
string m_fullPath = Path.Combine(i_path,i_GUID);
if(!File.Exists(m_fullPath)) return;
this.m_GUID = i_GUID;
this.m_uploadTime = System.DateTime.Now;
this.m_pathOnserver = i_path;
FileInfo m_fileInfo = new FileInfo(m_fullPath);
this.m_currentPoint = m_fileInfo.Length;
this.m_fileLength = i_fileLength;
}

public bool UploadData(byte[] i_data, long i_currentPoint, int i_dataSize)
{
string m_fullPath = this.FullPathOnServer;
if(!File.Exists(m_fullPath)&&this.m_currentPoint!=0)return false;
long m_filePoint = new FileInfo(m_fullPath).Length;
if(m_filePoint!=i_currentPoint) return false;
FileStream m_fileStream = new FileStream(m_fullPath,FileMode.Append);
m_fileStream.Write(i_data,0,i_dataSize);
m_fileStream.Close();
return true;
}

public void AbandantUpload()
{
string m_fullPath = this.FullPathOnServer;
try{File.Delete(m_fullPath);}
catch{}
}

public void CreateFile()
{
string m_fullPath = this.FullPathOnServer;
if(!File.Exists(m_fullPath))
{
File.Create(m_fullPath).Close();
}
else
{
try
{
File.Delete(m_fullPath);
}catch{}
File.Create(m_fullPath).Close();
}
}
}
}

这个是上传过程.

引用内容

#region UploadProcess
public void UploadProcess()
{
DateTime m_start = DateTime.Now;
this.textBox_OutMsg.AppendText("Initialize upload\r\n");
if(this.m_upload==null||this.m_uploadGUID==null||this.m_uploadGUID==string.Empty)
{
this.textBox_OutMsg.AppendText("Upload instance id error or login to the server faild\r\n");
this.textBox_OutMsg.AppendText("Upload faild.\r\n");
return;
}
this.textBox_OutMsg.AppendText("Open file\r\n");
if(this.m_filePath==null||this.m_filePath==string.Empty||!File.Exists(this.m_filePath))
{
this.textBox_OutMsg.AppendText("Open file error\r\n");
this.textBox_OutMsg.AppendText("Upload faild.\r\n");
return;
}
FileInfo m_fileInfo = new FileInfo(this.m_filePath);
FileStream m_fs = new FileStream(this.m_filePath, FileMode.Open, FileAccess.Read);
this.textBox_OutMsg.AppendText("Start upload file\r\n");
int m_buffer = 10; //KBytes
long m_currentPoint = 0;
long m_fileLength = m_fileInfo.Length;
bool m_uploadResult = false;
byte[] m_data = new byte[m_buffer*1024];
long m_readBytes = m_fs.Read(m_data, 0, m_buffer*1024);
this.UploadProcessBar.Maximum = 100;
this.UploadProcessBar.Minimum = 0;
while(m_readBytes>0)
{
MemoryStream m_memoryStream = new MemoryStream(m_data, 0,(int)m_readBytes);
DimeAttachment dimeAttach = new DimeAttachment("image/gif", TypeFormat.MediaType, m_memoryStream);
this.m_upload.RequestSoapContext.Attachments.Add(dimeAttach);
m_uploadResult = this.m_upload.UploadFileData(this.m_uploadInstance,m_currentPoint,m_readBytes);
if(m_uploadResult)
{
m_currentPoint +=m_readBytes;
m_readBytes = m_fs.Read(m_data,0,m_buffer*1024);
// this.textBox_OutMsg.AppendText("Uploading:"+m_currentPoint.ToString()+"/"+m_fileLength.ToString()+"\r\n");
this.UploadProcessBar.Value = (int)(m_currentPoint*100/m_fileLength);
this.label_outPercent.Text = this.UploadProcessBar.Value.ToString()+"%";
}
else
{
this.textBox_OutMsg.AppendText("Upload file error.\r\n");
m_fs.Close();
this.m_upload.AbandantUpload(this.m_uploadInstance);
return;
}
}
this.textBox_OutMsg.AppendText("File upload finished.\r\n");
this.button_Cancel.Enabled = false;
m_fs.Close();
this.ResetForm();
}
#endregion

原测试代码下载