using System;

using System.Collections.Generic;

using System.IO;

using System.Linq;

using System.Net;

using System.Text;

using System.Threading.Tasks;

namespace ConsoleApp1

{

  public static class SaveImgByUrl

  {

    /// <summary>

    /// 调用方法

    /// </summary>

    public static void SaveImg()

    {

      string imgurl = "https://img0.baidu.com/it/u=2229864841,4232235061&fm=26&fmt=auto";//图片地址

      string imgfile = "D:\\1.png";

      WriteBytesToFile(imgfile, GetBytesfromUrl(imgurl));

    }

    /// <summary>

    /// 将数据流转化为图片保存到本地

    /// </summary>

    /// <param name="fileName"></param>

    /// <param name="content"></param>

    static public void WriteBytesToFile(string fileName, byte[] content)

    {

      FileStream fs = new FileStream(fileName, FileMode.create);

      BinaryWriter w = new BinaryWriter(fs);

      try

      {

        w.Write(content);

      }

      finally

      {

        fs.Close();

        w.Close();

      }

    }

    /// <summary>

    /// 根据url将图片转化为数据流

    /// </summary>

    /// <param name="url"></param>

    /// <returns></returns>

    static public byte[] GetBytesfromUrl(string url)

    {

      byte[] b;

      HttpWebRequest myReq = (HttpWebRequest)WebRequest.create(url);

      WebResponse myResp = myReq.GetResponse();

      Stream stream = myResp.GetResponseStream();

      using (BinaryReader br = new BinaryReader(stream))

      {

        b = br.ReadBytes(500000);

        br.Close();

      }

      myResp.Close();

      return b;

    }

  }

}