本文实例讲述了C#使用HttpDownLoadHelper下载文件的方法。分享给大家供大家参考。具体实现方法如下：
using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.IO; using System.Threading;namespace ProjectWenDangManage.Framework { /// <summary> /// HTTP文件下载辅助类 /// </summary> public class HttpDownLoadHelper { /// <summary> /// 文件下载 /// </summary> /// <param name="_Request"></param> /// <param name="_Response"></param> /// <param name="_fileName">下载文件时的短文件名称</param> /// <param name="_fullPath">待下载文件的绝对路径</param> /// <param name="_speed">下载速度</param> /// <returns></returns> public static bool ResponseFile(HttpRequest _Request, HttpResponse _Response, string _fileName, string _fullPath, long _speed) { try { FileStream myFile = new FileStream(_fullPath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite); BinaryReader br = new BinaryReader(myFile); try { _Response.AddHeader("Accept-Ranges", "bytes"); _Response.Buffer = false; long fileLength = myFile.Length; long startBytes = 0;
double pack = 10240; //10K bytes //int sleep = 200; //每秒5次 即5*10K bytes每秒 int sleep = (int)Math.Floor(1000 * pack / _speed) + 1; if (_Request.Headers["Range"] != null) { _Response.StatusCode = 206; string[] range = _Request.Headers["Range"].Split(new char[] { '=', '-' }); startBytes = Convert.ToInt64(range[1]); } _Response.AddHeader("Content-Length", (fileLength - startBytes).ToString()); if (startBytes != 0) { //Response.AddHeader("Content-Range", string.Format(" bytes {0}-{1}/{2}", startBytes, fileLength-1, fileLength)); } _Response.AddHeader("Connection", "Keep-Alive"); _Response.ContentType = "application/octet-stream"; _Response.AddHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(_fileName, System.Text.Encoding.UTF8));
br.BaseStream.Seek(startBytes, SeekOrigin.Begin); int maxCount = (int)Math.Floor((fileLength - startBytes) / pack) + 1;
for (int i = 0; i < maxCount; i++) { if (_Response.IsClientConnected) { _Response.BinaryWrite(br.ReadBytes(int.Parse(pack.ToString()))); Thread.Sleep(sleep); } else { i = maxCount; } } return true; } catch { return false; } finally { br.Close();
myFile.Close(); } } catch { return false; } } } }
HttpDownLoadHelper
在webfrom中:
string filePath=Path.Combine(HttpRuntime.AppDomainAppPath,"Files","项目管理工具.msi"); HttpDownLoadHelper.ResponseFile(Request, Response, "下载显示的名称", filePath, 102400);
在mvc中:
string filePath=Path.Combine(HttpRuntime.AppDomainAppPath,"Files","项目管理工具.msi"); HttpDownLoadHelper.ResponseFile(HttpContext.ApplicationInstance.Context.Request, HttpContext.ApplicationInstance.Context.Response, "下载显示的名称", filePath, 102400);
希望本文所述对大家的C#程序设计有所帮助。