public void ProcessRequest(HttpContext context)
{
string strResponse = "0";
GetClass GetClass = new Common.CommonClass.GetClass();
GetClass.GetData = context.Request["GetData"];
dynamic getData = Common.NewtonJsonHelper.Deserialize <dynamic>(GetClass.GetData, null);
string path = getData.path;
string filePath = HttpContext.Current.Server.MapPath("~/" + path + "_temp");
System.IO.FileInfo fileInfo = new System.IO.FileInfo(filePath);
if (fileInfo.Exists)
{
strResponse = fileInfo.Length.ToString();
}
context.Response.ContentType = "text/plain";
context.Response.Write(strResponse);
}
int ChunkSize = 512 * 1024;//每次读取得大小
public void ProcessRequest(HttpContext context)
{
GetClass GetClass = new Common.CommonClass.GetClass();
GetClass.GetData = context.Request["GetData"];
dynamic getData = Common.NewtonJsonHelper.Deserialize <dynamic>(GetClass.GetData, null);
string name = getData.name;
string path = getData.path;
string filePath = HttpContext.Current.Server.MapPath("~/" + path);
System.IO.FileInfo fileInfo = new System.IO.FileInfo(filePath);
if (fileInfo.Exists)
{
byte[] buffer = new byte[ChunkSize];
context.Response.Clear();
System.IO.FileStream iStream = System.IO.File.OpenRead(filePath);
long dataLengthToRead = iStream.Length;//获得下载文件的总大小
long offset = 0, count = dataLengthToRead;
//处理按范围请求下载 开始字节-结束字节
if (context.Request.Headers.AllKeys.Contains("Range"))
{
var match = System.Text.RegularExpressions.Regex.Match(context.Request.Headers["Range"], @"(?<=bytes\b*=)(\d*)-(\d*)");
if (match.Success)
{
context.Response.StatusCode = (int)System.Net.HttpStatusCode.PartialContent;
string v1 = match.Groups[1].Value;
string v2 = match.Groups[2].Value;
if (!match.NextMatch().Success)
{
if (v1 == "" && v2 != "") //没有起始值，默认为0
{
var r2 = long.Parse(v2);
if (r2 <= count)
{
offset = 0;
count = r2;
//响应的格式是:Content-Range: bytes [文件块的开始字节]-[文件的总大小 - 1]/[文件的总大小]
context.Response.AddHeader("Content-Range", "bytes " + offset.ToString() + "-" + ((long)(dataLengthToRead - 1)).ToString() + "/" + dataLengthToRead.ToString());
context.Response.StatusCode = (int)System.Net.HttpStatusCode.PartialContent;
}
else //结束位置超界,返回零值
{
offset = 0;
count = 0;
context.Response.StatusCode = (int)System.Net.HttpStatusCode.RequestedRangeNotSatisfiable;
}
}
else if (v1 != "" && v2 == "")
{
var r1 = long.Parse(v1);
if (r1 > count)//起始位置超界,返回零值
{
offset = 0;
count = 0;
context.Response.StatusCode = (int)System.Net.HttpStatusCode.RequestedRangeNotSatisfiable;
}
else
{
offset = r1;
count -= r1;
//响应的格式是:Content-Range: bytes [文件块的开始字节]-[文件的总大小 - 1]/[文件的总大小]
context.Response.AddHeader("Content-Range", "bytes " + offset.ToString() + "-" + ((long)(dataLengthToRead - 1)).ToString() + "/" + dataLengthToRead.ToString());
context.Response.StatusCode = (int)System.Net.HttpStatusCode.PartialContent;
}
}
else if (v1 != "" && v2 != "")
{
var r1 = long.Parse(v1);
var r2 = long.Parse(v2);
if (r1 < count && r2 < count && r2 > r1)
{
offset = r1;
count -= r2 - r1 + 1;
//响应的格式是:Content-Range: bytes [文件块的开始字节]-[文件的总大小 - 1]/[文件的总大小]
context.Response.AddHeader("Content-Range", "bytes " + offset.ToString() + "-" + ((long)(dataLengthToRead - 1)).ToString() + "/" + dataLengthToRead.ToString());
context.Response.StatusCode = (int)System.Net.HttpStatusCode.PartialContent; //必须有，范围下载
}
else //范围出错,返回零值
{
offset = 0;
count = 0;
context.Response.StatusCode = (int)System.Net.HttpStatusCode.RequestedRangeNotSatisfiable;
}
}
else
{
context.Response.StatusCode = (int)System.Net.HttpStatusCode.OK;
}
}
}
}
iStream.Position = offset; //流起始位置
dataLengthToRead = count; //需要读的字节数
string[] fileNames = filePath.Split('\\');
string fileName = name;//fileNames[fileNames.Length - 1];
context.Response.ContentType = "application/octet-stream";
//通知浏览器下载文件而不是打开，中文转化编码
context.Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8));
context.Response.AppendHeader("Content-Length", dataLengthToRead.ToString()); //需要给出文件长度（需要都的字节数）（便于客户端使用，显示进度）
while (dataLengthToRead > 0 && context.Response.IsClientConnected)
{
int lengthRead = iStream.Read(buffer, 0, Convert.ToInt32(ChunkSize));//读取的大小
context.Response.OutputStream.Write(buffer, 0, lengthRead);
context.Response.Flush();
// context.Response.Clear();
dataLengthToRead = dataLengthToRead - lengthRead;
}
iStream.Close();
context.Response.End();
context.Response.Close();
}
else
{
HttpContext.Current.Response.Write("文件不存在");
}
}
