本文为大家分享了HttpWebRequest实现下载图片至本地的具体代码，供大家参考，具体内容如下
HttpWebRequest发送web请求，获取流文件，保存至本地
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 | using System;using System.IO;using System.Net;using System.Text;using System.Web.Mvc; namespace Web.Controllers{ public class HomeController : Controller { string url = "http://www.***.com/Image.aspx?ucode=ucode"; public Stream GetFileToStream(string filePath) { FileStream fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read); byte[] bytes = new byte[fileStream.Length]; fileStream.Read(bytes, 0, bytes.Length); fileStream.Close(); Stream streamFile = new MemoryStream(bytes); return streamFile; } public void Method1() { string fileName = @"\upload\" + GenerateTimeStamp() + ".jpg"; string webPath = Server.MapPath(fileName); string pathName = @"d:\" + GenerateTimeStamp() + ".jpg"; HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url); req.ServicePoint.Expect100Continue = false; req.Method = "GET"; req.KeepAlive = true; req.ContentType = "image/png"; HttpWebResponse rsp = (HttpWebResponse)req.GetResponse(); System.IO.Stream stream = null; try { //以字符流的方式读取HTTP响应 stream = rsp.GetResponseStream(); System.Drawing.Image.FromStream(stream).Save(pathName); } finally { // 释放资源 if (stream != null) stream.Close(); if (rsp != null) rsp.Close(); } } protected void Method2() { string fileName = @"\upload\" + GenerateTimeStamp() + ".jpg"; string webPath = Server.MapPath(fileName); string pathName = @"d:\" + GenerateTimeStamp() + ".jpg"; HttpWebRequest myRequest = (HttpWebRequest)WebRequest.Create(url); myRequest.Method = "GET"; HttpWebResponse myResponse = null; try { myResponse = (HttpWebResponse)myRequest.GetResponse(); StreamReader reader = new StreamReader(myResponse.GetResponseStream(), Encoding.UTF8); Stream stream = myResponse.GetResponseStream(); #region 保存下载图片 MemoryStream ms = null; Byte[] buffer = new Byte[myResponse.ContentLength]; int offset = 0, actuallyRead = 0; do { actuallyRead = stream.Read(buffer, offset, buffer.Length - offset); offset += actuallyRead; } while (actuallyRead > 0); ms = new MemoryStream(buffer); byte[] buffurPic = ms.ToArray(); System.IO.File.WriteAllBytes(pathName, buffurPic); #endregion } //异常请求 catch (WebException ex) { } } protected void Method3() { string fileName = @"\upload\" + GenerateTimeStamp() + ".jpg"; string webPath = Server.MapPath(fileName); string pathName = @"d:\" + GenerateTimeStamp() + ".jpg"; HttpWebRequest myRequest = (HttpWebRequest)WebRequest.Create(url); myRequest.Method = "GET"; HttpWebResponse myResponse = null; try { myResponse = (HttpWebResponse)myRequest.GetResponse(); StreamReader reader = new StreamReader(myResponse.GetResponseStream(), Encoding.UTF8); Stream stream = myResponse.GetResponseStream(); #region 保存下载图片 FileStream fileStream = new FileStream(pathName, FileMode.Create, FileAccess.Write); byte[] bytes = new byte[1024]; int readSize = 0; while ((readSize = stream.Read(bytes, 0, 1024)) > 0) { fileStream.Write(bytes, 0, readSize); fileStream.Flush(); } #endregion myResponse.Close(); stream.Close(); fileStream.Close(); } //异常请求 catch (WebException ex) { } finally { } } public string GenerateTimeStamp() { TimeSpan ts = DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0, 0); return Convert.ToInt64(ts.TotalMilliseconds).ToString(); } }} |
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持服务器之家。
