C#完成文件斷點續傳下載的辦法。本站提示廣大學習愛好者:(C#完成文件斷點續傳下載的辦法)文章只能為提供參考,不一定能成為您想要的結果。以下是C#完成文件斷點續傳下載的辦法正文
本文實例講述了C#完成文件斷點續傳下載的辦法。分享給年夜家供年夜家參考。詳細完成辦法以下:
using System; using System.Data; using System.Configuration; using System.Web; using System.Web.Security; using System.IO; using System.Text; using System.Net; namespace simpleDemo { class Program { /// <summary> /// 下載文件保存字 /// </summary> public static string PERSIST_EXP = ".cdel"; /// <summary> public static void Main(string[] args) { string path = "D:\\aa.txt"; string ec = getFileEncoding(path, "GB2312"); print("coding: " + ec); // string content = fileReader(path, Encoding.GetEncoding(ec)); // print(content); //fileWriter(path, "測試內容11", Encoding.GetEncoding(ec)); string url = "http://www.XXX.com/20120920172200024.flv"; string path1 = "D:\\aa1.flv"; download(url, path1); //gapDownload(url, path1); //t(url); } public static void t(string url) { HttpWebRequest request = (System.Net.HttpWebRequest)HttpWebRequest.Create(url); //WebResponse response = httpClient.CreateGetHttpResponse(url, 3000, null, null); try { WebResponse response = request.GetResponse(); WebHeaderCollection headers = response.Headers; print(response.ContentLength); request = (System.Net.HttpWebRequest)HttpWebRequest.Create(url); request.AddRange(11); //設置Range值 WebResponse response1 = request.GetResponse(); print(response1.ContentLength); foreach (string key in headers) { print(key + "----- " + headers.Get(key)); } string disposition = headers.Get("Content-Disposition"); print(disposition); }catch(Exception e){ print(e.Message); } //string fileName = disposition.Substring(disposition.IndexOf("\"")); //print(fileName); } public static void download(string url, string path) { if (File.Exists(path)) { print("文件己存在!能否從新下載?"); return; } else { path = path + PERSIST_EXP; simpleDownload(url,path);//開端下載 } } /// <summary> /// 下載收集資本(支撐斷點續傳) /// </summary> /// <param name="url"></param> /// <param name="path"></param> public static void simpleDownload(string url, string path) { HttpWebRequest request = httpClient.getWebRequest(url, 0); WebResponse response = null; FileStream writer = new FileStream(path, FileMode.OpenOrCreate, FileAccess.Write); long lStartPos = writer.Length; ;//以後文件年夜小 long currentLength = 0; long totalLength = 0;//總年夜小 if (File.Exists(path))//斷點續傳 { response = request.GetResponse(); long sTotal = response.ContentLength; if (sTotal == lStartPos) { close(writer); File.Move(path, path.WordStr(PERSIST_EXP, "")); print("下載完成!"); return; } request = httpClient.getWebRequest(url, (int)lStartPos); //設置Range值 writer.Seek(lStartPos, SeekOrigin.Begin);//指針跳轉 response = request.GetResponse(); totalLength = response.ContentLength + lStartPos; //總長度 currentLength = lStartPos; //以後長度 } else { response = request.GetResponse(); totalLength = response.ContentLength; } Stream reader = response.GetResponseStream(); byte[] buff = new byte[1024]; int c = 0; //現實讀取的字節數 while ((c = reader.Read(buff, 0, buff.Length)) > 0) { currentLength += c; writer.Write(buff, 0, c); progressBar(currentLength, totalLength);//進度條 writer.Flush(); } close(writer); if (currentLength == totalLength) { File.Move(path, path.WordStr(PERSIST_EXP, "")); print("下載完成!"); } if (reader != null) { reader.Close(); reader.Dispose(); response.Close(); } } private static void close(FileStream writer) { if (writer != null) { writer.Close(); writer.Dispose(); } } /// <summary> /// 進度條 /// </summary> /// <param name="currentLength">以後長度</param> /// <param name="totalLength">總長度</param> public static void progressBar(Object currentLength, Object totalLength) { double aaa = System.Convert.ToDouble(currentLength); double bbb = System.Convert.ToDouble(totalLength); print(currentLength + "/" + totalLength + "__" + (aaa / bbb).ToString("0.00 %")); } /// <summary> /// 體系輸入 /// </summary> /// <param name="obj"></param> public static void print(Object obj){ Console.WriteLine(obj); } public static void printStr(string[] str) { foreach (string d in str) { print(d); } } /// <summary> /// 文件寫 /// </summary> /// <param name="path">文件途徑</param> /// <param name="content">要寫入的內容</param> public static void fileWriter(string path,string content,Encoding encoding) { if (File.Exists(path)) { StreamWriter sw = new StreamWriter(path, true, encoding); sw.WriteLine(content); sw.Flush(); sw.Close(); } } /// <summary> /// 讀文件,前往內容 /// </summary> /// <param name="path">文件途徑</param> /// <param name="enCoding">默許編碼格局</param> /// <returns></returns> public static string fileReader(string path,Encoding enCoding) { StringBuilder sb = new StringBuilder(); if(enCoding == null){ enCoding = Encoding.Default; } //讀取文件 StreamReader sr = new StreamReader(path, enCoding); string s = ""; while ((s = sr.ReadLine()) != null) { sb.AppendLine(s); } if(sr != null) sr.Close(); return sb.ToString(); } /// <summary> /// 獲得文件編碼格局 /// </summary> /// <param name="path">文件途徑</param> /// <param name="defaultEncoding">默許編碼</param> /// <returns></returns> public static string getFileEncoding(string path, string defaultEncoding) { string ed = defaultEncoding; if (File.Exists(path)) { FileStream fs = new FileStream(path, FileMode.Open); ed = GetEncoding(fs, defaultEncoding); if (fs != null) fs.Close(); } return ed; } /// <summary> /// 獲得一個文本文件流的編碼方法。 /// </summary> /// <param name="stream">文本文件流。</param> /// <param name="defaultEncoding">默許編碼方法。當該辦法沒法從文件的頭部獲得有用的前導符時,將前往該編碼方法。</param> /// <returns></returns> public static string GetEncoding(FileStream stream, string defaultEncoding) { string targetEncoding = defaultEncoding; if (stream != null && stream.Length >= 2) { //保留文件流的前4個字節 byte byte1 = 0; byte byte2 = 0; byte byte3 = 0; byte byte4 = 0; //保留以後Seek地位 long origPos = stream.Seek(0, SeekOrigin.Begin); stream.Seek(0, SeekOrigin.Begin); int nByte = stream.ReadByte(); byte1 = Convert.ToByte(nByte); byte2 = Convert.ToByte(stream.ReadByte()); if (stream.Length >= 3) { byte3 = Convert.ToByte(stream.ReadByte()); } if (stream.Length >= 4) { byte4 = Convert.ToByte(stream.ReadByte()); } //依據文件流的前4個字節斷定Encoding //Unicode {0xFF, 0xFE}; //BE-Unicode {0xFE, 0xFF}; //UTF8 = {0xEF, 0xBB, 0xBF}; if (byte1 == 0xFE && byte2 == 0xFF)//UnicodeBe { targetEncoding = Encoding.BigEndianUnicode.BodyName; } if (byte1 == 0xFF && byte2 == 0xFE && byte3 != 0xFF)//Unicode { targetEncoding = Encoding.Unicode.BodyName; } if (byte1 == 0xEF && byte2 == 0xBB && byte3 == 0xBF)//UTF8 { targetEncoding = Encoding.UTF8.BodyName; } //恢復Seek地位 stream.Seek(origPos, SeekOrigin.Begin); } return targetEncoding; } } } using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Net; using System.Net.Security; using System.Security.Cryptography.X509Certificates; using System.IO; namespace simpleDemo { /// <summary> /// 公用 Http 要求類 /// </summary> class httpClient { /// <summary> /// 獲得基本WebRequest /// </summary> /// <param name="url">要求地址</param> /// <param name="lStartPos">要求的開端地位</param> /// <returns></returns> public static HttpWebRequest getWebRequest(string url, int lStartPos) { HttpWebRequest request = null; try { request = (System.Net.HttpWebRequest)HttpWebRequest.Create(url); request.AddRange(lStartPos); //設置Range值 } catch (Exception ex) { Program.print(ex.Message); } return request; } } }
願望本文所述對年夜家的C#法式設計有所贊助。