C#开发下载器，常用的下载方式有那些？

Question

常用的都有什么下载方式，各有什么优缺点。谢谢！！！
c#下载

Answer 1

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.IO;public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{}//TransmitFile实现下载
protected void Button1_Click(object sender, EventArgs e)
{
Response.ContentType = "application/x-zip-compressed";
Response.AddHeader("Content-Disposition", "attachment;filename=z.zip");
string filename = Server.MapPath("DownLoad/z.zip");
Response.TransmitFile(filename);
}//WriteFile实现下载
protected void Button2_Click(object sender, EventArgs e)
{
string fileName ="asd.txt";//客户端保存的文件名
string filePath=Server.MapPath("DownLoad/aaa.txt");//路径FileInfo fileInfo = new FileInfo(filePath);
Response.Clear();
Response.ClearContent();
Response.ClearHeaders();
Response.AddHeader("Content-Disposition", "attachment;filename=" + fileName);
Response.AddHeader("Content-Length", fileInfo.Length.ToString());
Response.AddHeader("Content-Transfer-Encoding", "binary");
Response.ContentType = "application/octet-stream";
Response.ContentEncoding = System.Text.Encoding.GetEncoding("gb2312");
Response.WriteFile(fileInfo.FullName);
Response.Flush();
Response.End();
}//WriteFile分块下载
protected void Button3_Click(object sender, EventArgs e)
{string fileName = "aaa.txt";//客户端保存的文件名
string filePath = Server.MapPath("DownLoad/aaa.txt");//路径System.IO.FileInfo fileInfo = new System.IO.FileInfo(filePath);if (fileInfo.Exists == true)
{
const long ChunkSize = 102400;//100K 每次读取文件，只读取100K，这样可以缓解服务器的压力
byte[] buffer = new byte[ChunkSize];Response.Clear();
System.IO.FileStream iStream = System.IO.File.OpenRead(filePath);
long dataLengthToRead = iStream.Length;//获取下载的文件总大小
Response.ContentType = "application/octet-stream";
Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName));
while (dataLengthToRead > 0 && Response.IsClientConnected)
{
int lengthRead = iStream.Read(buffer, 0, Convert.ToInt32(ChunkSize));//读取的大小
Response.OutputStream.Write(buffer, 0, lengthRead);
Response.Flush();
dataLengthToRead = dataLengthToRead - lengthRead;
}
Response.Close();
}
}//流方式下载
protected void Button4_Click(object sender, EventArgs e)
{
string fileName = "aaa.txt";//客户端保存的文件名
string filePath = Server.MapPath("DownLoad/aaa.txt");//路径//以字符流的形式下载文件
FileStream fs = new FileStream(filePath, FileMode.Open);
byte[] bytes = new byte[(int)fs.Length];
fs.Read(bytes, 0, bytes.Length);
fs.Close();
Response.ContentType = "application/octet-stream";
//通知浏览器下载文件而不是打开
Response.AddHeader("Content-Disposition", "attachment;  filename=" + HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8));
Response.BinaryWrite(bytes);
Response.Flush();
Response.End();}
}

Answer 2

 /// <summary>
        /// 下载文件，无续传功能
        /// </summary>
        /// <param name="SaveFilePath">文件完整保存路径</param>
        /// <param name="UpdaterUrl">文件下载地址</param>
        /// <returns></returns>
        private bool DownFileUnContinue(string SaveFilePath, string UpdaterUrl)
        {
            if (!System.IO.Directory.Exists(Path.GetDirectoryName(SaveFilePath)))
                System.IO.Directory.CreateDirectory(Path.GetDirectoryName(SaveFilePath));            try
            {
                WebRequest req = WebRequest.Create(UpdaterUrl);
                req.Timeout = 10000;
                req.Method = "HEAD";
                WebResponse res = req.GetResponse();
                if (res.ContentLength > 0)
                {
                    try
                    {
                        WebClient wClient = new WebClient();
                        wClient.DownloadFile(UpdaterUrl, SaveFilePath);
                        wClient.Dispose();
                        return true;
                    }
                    catch (Exception ex)
                    {
                        throw ex;
                    }
                    finally
                    {
                        res.Close();
                    }
                }
                else
                {
                    SetRate(-1);
                    return false;
                }
            }
            catch (Exception ex)
            {
                return false;
            }
        }

Answer 3

FTP、HTTP、WCF直连，其中WCF需要设计服务端。而前面2者服务端都是标准的，不需要考虑。