雷火电竞-中国电竞赛事及体育赛事平台

歡迎來到入門教程網(wǎng)!

C#教程

當前位置:主頁 > 軟件編程 > C#教程 >

HttpWebRequest實現(xiàn)下載圖片至本地

來源:本站原創(chuàng)|時間:2020-01-10|欄目:C#教程|點擊:

本文為大家分享了HttpWebRequest實現(xiàn)下載圖片至本地的具體代碼,供大家參考,具體內(nèi)容如下

HttpWebRequest發(fā)送web請求,獲取流文件,保存至本地

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
      {
        //以字符流的方式讀取HTTP響應
        stream = rsp.GetResponseStream();
        System.Drawing.Image.FromStream(stream).Save(pathName);
      }
      finally
      {
        // 釋放資源
        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 保存下載圖片
 
        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
      }
      //異常請求
      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 保存下載圖片
 
        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();
      }
      //異常請求
      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內(nèi)容,希望對大家的學習有所幫助,也希望大家多多支持我們。

上一篇:C# 7.0中解構(gòu)功能詳解

欄    目:C#教程

下一篇:C# 獲取 PC 序列號的方法示例

本文標題:HttpWebRequest實現(xiàn)下載圖片至本地

本文地址:http://www.jygsgssxh.com/a1/C_jiaocheng/5114.html

網(wǎng)頁制作CMS教程網(wǎng)絡編程軟件編程腳本語言數(shù)據(jù)庫服務器

如果侵犯了您的權(quán)利,請與我們聯(lián)系,我們將在24小時內(nèi)進行處理、任何非本站因素導致的法律后果,本站均不負任何責任。

聯(lián)系QQ:835971066 | 郵箱:835971066#qq.com(#換成@)

Copyright © 2002-2020 腳本教程網(wǎng) 版權(quán)所有