脑残的FtpWebRequest 2之事故现场重现

鉴于上一篇POST过于抽象以至于很多人无法理解，现在用代码来说话，我们一起来重新回顾一下事故现场的情况。

首先在本机安装FTP软件，我这里使用的Serv-U一个用得非常广泛的Ftp Server，准备好Ftp的目录，我这里使用自己放mp3的目录

其中有一个子目录 2

我们可以看到两个目录的内容截然不同以方便我们重现事故现场。

第二部我们建立一个Winform项目

之后在界面上用三个按钮来实现testCase

第三步是准备的重头戏，我们准备一个Ftp的操作类：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.IO;

namespace TestFtpWebRequest
{
    class FtpHelper
    {
        public static void Upload(string Url, string LocalPath)
        {
            FileInfo f = new FileInfo(LocalPath);
            FtpWebRequest req = (FtpWebRequest)FtpWebRequest.Create(Url + "/" + f.Name);
            req.Credentials = new NetworkCredential("Test", "123456");
            req.Method = WebRequestMethods.Ftp.UploadFile;
            req.UseBinary = true;
            req.ContentLength = f.Length;
            FtpWebResponse rep = (FtpWebResponse)req.GetResponse();
            using (Stream s = req.GetRequestStream())
            {
                using (FileStream fs = f.OpenRead())
                {
                    int readcount = 0;
                    long totalread = 0;
                    byte[] buffer = new byte[1024];
                    while (true)
                    {
                        readcount = fs.Read(buffer, 0, 1024);
                        totalread += readcount;
                        s.Write(buffer, 0, readcount);
                        if (totalread >= f.Length)
                        {
                            break;
                        }
                    }

                }
            }
        }
        public static string[] List(string Url)
        {
            List<string> rs = new List<string>();
            FtpWebRequest req = (FtpWebRequest)FtpWebRequest.Create(Url);
            req.Credentials = new NetworkCredential("Test", "123456");
            req.Method = WebRequestMethods.Ftp.ListDirectory;
            FtpWebResponse rep = (FtpWebResponse)req.GetResponse();
            long len = rep.ContentLength;
            using (Stream s = rep.GetResponseStream())
            {
                MemoryStream ms = new MemoryStream();
                int readcount = 0;
                long totalcount = 0;
                byte[] buffer = new byte[1024];
                while (true)
                {
                    readcount = s.Read(buffer, 0, 1024);
                    totalcount += readcount;
                    ms.Write(buffer, 0, readcount);
                    if (totalcount >= len)
                    {
                        break;
                    }
                }
                s.Close();
                rep.Close();
                string str = Encoding.Default.GetString(ms.ToArray());
                StringReader sr = new StringReader(str);
                string line = string.Empty;
                while ((line = sr.ReadLine()) != null)
                {
                    rs.Add(line);
                }
            }
            return rs.ToArray();
        }
    }
}

这里准备了两个操作方法，一个是读取文件列表，一个是上传文件

最后在按钮里写上调用的方法

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace TestFtpWebRequest
{
    public partial class Form1 : Form
    {
        const string Path1 = @"D:\MyDocument\test.jpg";
        const string Path2 = @"D:\MyDocument\yoxi.jpg";
        const string FtpUrl = "ftp://192.168.212.102";
        const string FtpUrl2 = "ftp://192.168.212.102/2";

        public Form1()
        {
            InitializeComponent();
        }

        private void button3_Click(object sender, EventArgs e)
        {
            textBox1.Text = string.Empty;
            string[] files = FtpHelper.List(FtpUrl);

            textBox1.Text = "file count:" + files.Length + "\r\n";
            foreach (string s in files)
            {
                textBox1.Text += "ftp:" + s + "\r\n";
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            FtpHelper.Upload(FtpUrl2, Path1);
            MessageBox.Show("up ok!");
        }

        private void button2_Click(object sender, EventArgs e)
        {
            FtpHelper.Upload(FtpUrl2, Path2);
            MessageBox.Show("up ok!");
        }
    }
}

好了，根据两个ftp的方法大家可以看到，从表面上两个方法应该是独立的，不管在什么时候，我如果按列表的按钮都应该返回Ftp根目录的文件列表出来。但是实际的执行结果，我们拭目以待。

首先我们执行程序，点击列表按钮(List with no upload)，这个时候我们能够看到返回的确实是根目录的文件