FTP Class not used

问题:

today I tried C# for the first time. I want to upload a folder to an FTP Server and used this FTP CLass: http://www.codeproject.com/Tips/443588/Simple-Csharp-FTP-Class

Now, when I use the Methods, it Says "Name ftpClient does not exist in that context". I will copy my code:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Net
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;


namespace DaloCloud
{

    public partial class Form1 : Form
    {
        static int x = 200;     // For Help-Screen
        static int y = 200;     // For Help-Screen
        string username;        // FTP-Username Value stored in there
        string password;        // FTP-Password Value stored in there
        string dirPath;         // C:\DaloUpload
        string uploadPath;       // ftp: //daloserver/users/username/files

        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void pictureBox1_Click(object sender, EventArgs e)
        {

        }

        private void helpButton_Click(object sender, EventArgs e)
        {
            // Create a new instance of Form2 and set its Visible property to true.
            Form2 form2 = new Form2();
            form2.Visible = true;

        }

        private void usernameTextbox_TextChanged(object sender, EventArgs e)
        {
            username = usernameTextbox.Text;
        }

        private void passwordTextbox_TextChanged(object sender, EventArgs e)
        {
            password = passwordTextbox.Text;
        }

        private void connectButton_Click(object sender, EventArgs e)
        {
            string[] files = Directory.GetFiles(dirPath, "*.*");
            string[] subDirs = Directory.GetDirectories(dirPath);

            foreach (string file in files)
            {
                ftpClient.upload(uploadPath + "/" + Path.GetFileName(file), file);
            }

            foreach (string subDir in subDirs)
            {
                ftpClient.createDirectory(uploadPath + "/" + Path.GetFileName(subDir));
                recursiveDirectory(subDir, uploadPath + "/" + Path.GetFileName(subDir));
            }
        }
    }
}

回答1:

In C#, you have to declare variables before you can use them. You haven't declared any variable named ftpClient.

This error is telling you quite concisely that ftpClient doesn't exist at the point you are using it. You must declare it to make it exist.

Might looks something like this:

FTPClient ftpClient = new FTPClient();