.net网站的文件上传读取进度条和断点下载

UpfileResult result = new UpfileResult();
try
{
//直接使用request.Files读取，是无法计算进度的。需要主动操作文件流的读取，同时计算上传进度
IServiceProvider provider = HttpContext.Current;
HttpWorkerRequest request = (HttpWorkerRequest)provider.GetService(typeof(HttpWorkerRequest)); // 获取请求正文的大小
long length = long.Parse(request.GetKnownRequestHeader(HttpWorkerRequest.HeaderContentLength));
CheckFileSize(length, upfileConfig); int bytesRead = 0; // 已读数据大小
int readSize; // 当前读取的块的大小
int packSize = 1024 * 10;
byte[] buffer;
byte[] tempBuff;
if (request.IsClientConnected() && !request.IsEntireEntityBodyIsPreloaded())
{
buffer = new byte[length]; //http请求正文已被读取的部分
tempBuff = request.GetPreloadedEntityBody();
// 将已读取数据复制过来
Buffer.BlockCopy(tempBuff, 0, buffer, bytesRead, tempBuff.Length); // 开始记录已读取大小
bytesRead = tempBuff.Length; //计算当前上传文件的百分比
long percent = (long)bytesRead * 100 / length;
SetPercent(SessionId, percent); int ii = 0;
tempBuff = new byte[packSize];
// 循环分块读取，直到所有数据读取结束
while (request.IsClientConnected() && !request.IsEntireEntityBodyIsPreloaded())
{
// 分块读取
readSize = request.ReadEntityBody(tempBuff, packSize);
// 复制已读数据块
Buffer.BlockCopy(tempBuff, 0, buffer, bytesRead, readSize);
// 记录已上传大小
bytesRead += readSize;
ii++;
if (ii % 30 == 0)//每300kb更新一次进度
{
//计算当前上传文件的百分比
percent = (long)bytesRead * 100 / length;
SetPercent(SessionId, percent);
}
if (readSize == 0)
{
break;
}
}if (!request.IsEntireEntityBodyIsPreloaded())
{
//如果当前状态依然是没有读取完全，通过反射更新预读内容
BindingFlags bindingFlags = BindingFlags.Instance | BindingFlags.NonPublic;
Type type = request.GetType();
while (type != null
&& type.FullName != "System.Web.Hosting.ISAPIWorkerRequest"
&& type.FullName != "System.Web.Hosting.IIS7WorkerRequest")
{
type = type.BaseType;
}if (type != null)
{
if (type.FullName == "System.Web.Hosting.ISAPIWorkerRequest")
{
type.GetField("_contentAvailLength", bindingFlags).SetValue(request, buffer.Length);
type.GetField("_contentTotalLength", bindingFlags).SetValue(request, buffer.Length);
type.GetField("_preloadedContent", bindingFlags).SetValue(request, buffer);
type.GetField("_preloadedContentRead", bindingFlags).SetValue(request, true);
}
else
{
type.GetField("_contentTotalLength", bindingFlags).SetValue(request, buffer.Length);
type.GetField("_preloadedContent", bindingFlags).SetValue(request, buffer);
type.GetField("_preloadedContentRead", bindingFlags).SetValue(request, true);
type.GetField("_preloadedLengthRead", bindingFlags).SetValue(request, true);
type.GetField("_preloadedLength", bindingFlags).SetValue(request, buffer.Length);
}
}
}
}
HttpPostedFile imgFile = _request.Files[0];
string fileName = imgFile.FileName;
UpLoadFile(result, imgFile, fileName, upfileConfig, SessionId);
return result;
}
catch (Exception ex)
{
SetPercent(SessionId, 100);
result.IsOk = false;
result.ErrMsg = ex.Message;
return result;
}

/// <summary>
/// 支持断点下载
/// </summary>
/// <param name="Request"></param>
/// <param name="Response"></param>
/// <param name="filePath">文件的物理地址</param>
private void Down(HttpRequest Request, HttpResponse Response, string filePath)
{
/*断点下载与普通模式不一样的是：
断点下载的请求头信息里面增加一个属性 RANGE: bytes=100000-
响应头里 增加一个属性 Content-Range=bytes 100000-19999/20000
返回状态码为206(Partial Content) 表示头500个字节：Range: bytes=0-499
表示第二个500字节：Range: bytes=500-999
表示最后500个字节：Range: bytes=-500
表示500字节以后的范围：Range: bytes=500-
第一个和最后一个字节：Range: bytes=0-0,-1
同时指定几个范围：Range: bytes=500-600,601-999
*/ // 打开文件
using (Stream fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read))
{
// 获取文件的大小
long fileSize = fileStream.Length;
string range = Request.Headers["Range"]; Response.Clear();
Response.AddHeader("Accept-Ranges", "bytes");
Response.AddHeader("Connection", "Keep-Alive");
Response.Buffer = false; //数据包大小
int pack = 10240; //10Kb
int sleep = 0;
if(this.Speed.HasValue)
{
sleep = (int)Math.Floor(1000.0 * 10 / this.Speed.Value);
} long begin = 0;
long end = fileSize - 1; if (!string.IsNullOrEmpty(range))
{
//获取请求的范围，如果有多个范围，暂时只处理第一个，Range: bytes=500-600,601-999
range = range.Replace("bytes=", "");
range = range.Split(',')[0];
string[] region = range.Split('-');
string startPoint = region[0].Trim();
string endPoint = region[1].Trim();
if (startPoint == "")
{
long.TryParse(endPoint, out end);
begin = fileSize - end;
end = fileSize - 1;
}
else if (endPoint == "")
{
long.TryParse(startPoint, out begin);
end = fileSize - 1;
}
else
{
long.TryParse(startPoint, out begin);
long.TryParse(endPoint, out end);
} Response.StatusCode = 206;
Response.AddHeader("Content-Range", string.Format("bytes {0}-{1}/{2}", begin, end, fileSize));
}
//以字节流返回数据
Response.ContentType = "application/octet-stream";
Response.AddHeader("Content-Disposition"
, "attachment; filename=\"" + HttpUtility.UrlEncode(Request.ContentEncoding.GetBytes(this.FileName)) + "\""); long size = end - begin + 1;
Response.AddHeader("Content-Length", size.ToString()); // 创建一比特数组
byte[] buffer = new Byte[pack];
fileStream.Position = begin; //设置当前流位置
// 当文件大小大于0是进入循环
while (size > 0)
{
// 判断客户端是否仍连接在服务器
if (Response.IsClientConnected)
{
int length = fileStream.Read(buffer, 0, pack);
Response.OutputStream.Write(buffer, 0, length);
// 将缓冲区的输出发送到客户端
Response.Flush(); size = size - length;
if (sleep > 0)
{
Thread.Sleep(sleep);
}
}
else
{
//当用户断开后退出循环
size = -1;
}
}
}
}

<system.web>
<httpRuntime maxRequestLength="2097151" executionTimeout="5600" useFullyQualifiedRedirectUrl="true" />
</system.web><system.webServer>
<security>
<requestFiltering>
<requestLimits maxAllowedContentLength="100000000"/>
</requestFiltering>
</security>
</system.webServer>