public static HttpHeaderVariable Init(HttpRequestBase request)
{
HttpHeaderVariable r = new HttpHeaderVariable();
r.Range = new ContentRange();
var ifRanges = request.Headers.GetValues("If-Range");
if (ifRanges != null)
{
r.IsContanisIfRange = true;
r.IfRangeString = ifRanges[0];
}
var ifModifies = request.Headers.GetValues("If-Modified-Since");
if (ifModifies != null)
{
r.IsContainsModify = true;
r.SinceModify = Convert.ToDateTime(ifModifies[0]);
}
var ifUnmodifies = request.Headers.GetValues("If-Unmodified-Since");
if (ifUnmodifies != null)
{
r.IsContainsUnmodified = true;
r.SinceUnmodify = Convert.ToDateTime(ifUnmodifies[0]);
}
var ranges = request.Headers.GetValues("Range");
if (ranges != null)
{
r.IsContainsRange = true;
var range = ranges[0];
int indexD = range.IndexOf('=');
int indexJ = range.IndexOf('-');
r.Range.Start = Convert.ToInt32(range.Substring(indexD + 1, indexJ - indexD - 1));
if (indexJ == range.Length - 1)
{
r.Range.End = 0;
}
else
{
r.Range.End = Convert.ToInt32(range.Substring(indexJ + 1, range.Length - indexJ - 1));
}
}
return(r);
}
/// <summary>
/// 播放或者下载视频都可以调这个方法
/// </summary>
/// <param name="path"></param>
/// <param name="Request"></param>
/// <param name="Response"></param>
public static void PlayOrDownloadVideo(string path, HttpRequestBase Request, HttpResponseBase Response)
{
FileStream stm = null;
try
{
Response.CacheControl = "public";
FileInfo fi = new FileInfo(path);
stm = new FileStream(fi.FullName, FileMode.Open, FileAccess.Read);
var vary = HttpHeaderVariable.Init(Request);
vary.Range.Total = fi.Length;
if (vary.Range.End == 0 || vary.Range.End > vary.Range.Total - 1)
{
vary.Range.End = vary.Range.Total - 1;
}
if (vary.IsContainsModify)
{
if (fi.LastWriteTimeUtc <= vary.SinceModify)
{
Response.StatusCode = 304;
Response.Headers.Add("Etag", GetEtag(fi));
Response.End();
}
}
if (vary.IsContanisIfRange)
{
if (GetEtag(fi) == vary.IfRangeString)
{
Response.StatusCode = 206;
Response.Headers.Add("Etag", GetEtag(fi));
}//get all
else
{
vary.Range.Start = 0;
vary.Range.End = vary.Range.Total - 1;
}
}
if (vary.IsContainsRange)
{
Response.StatusCode = 206;
}
else
{
Response.StatusCode = 200;
}
Response.AddHeader("Accept-Ranges", "bytes");
Response.AddHeader("Connection", "keep-alive");
Response.AddHeader("Content-Length", vary.Range.Length.ToString());
Response.AddHeader("Content-Range", string.Format("bytes {0}-{1}/{2}", vary.Range.Start, vary.Range.End, vary.Range.Total));
Response.ContentType = "video/mp4";
Response.Cache.SetMaxAge(TimeSpan.FromHours(1));
Response.Cache.SetETag(GetEtag(fi));
Response.Cache.SetExpires(DateTime.Now.AddDays(3));
Response.Cache.SetLastModified(fi.LastWriteTime);
stm.Position = vary.Range.Start;
long totalLength = vary.Range.Length;
var buffer = new byte[1024];
int n = 1;
while (totalLength > 0 && n > 0)
{
n = stm.Read(buffer, 0, (int)Math.Min(totalLength, buffer.Length));
Response.OutputStream.Write(buffer, 0, n);
totalLength -= n;
}
}
finally
{
if (stm != null)
{
stm.Dispose();
}
Response.End();
}
}
