C# SFTP Implementation

To implement SFTP file transfer in C#, you can use a third-party library called SSH.NET. Here is a simple example:

1. Firstly, the SSH.NET library needs to be installed. You can search for SSH.NET in the NuGet Package Manager and install it.
2. Create a new C# console application and incorporate the SSH.NET library.

using Renci.SshNet;

1. Write code to achieve SFTP file transfer.

class Program
{
    static void Main(string[] args)
    {
        // 连接SFTP服务器
        using (var client = new SftpClient("sftp.example.com", "username", "password"))
        {
            client.Connect();

            // 上传文件
            using (var fileStream = System.IO.File.OpenRead("localfile.txt"))
            {
                client.UploadFile(fileStream, "/remote/path/remoteFile.txt");
            }

            // 下载文件
            using (var fileStream = System.IO.File.Create("localfile.txt"))
            {
                client.DownloadFile("/remote/path/remoteFile.txt", fileStream);
            }

            client.Disconnect();
        }
    }
}

In the example above, first create an SftpClient object and connect to the SFTP server with connection information. Then upload a local file to the remote server using the UploadFile method, and download a file from the remote server to the local machine using the DownloadFile method.

It is important to note that the server address, username, password, and file path in the sample code need to be replaced. Additionally, handling exceptions is necessary to ensure the stability and security of file transmission.

Here is a simple example of implementing SFTP file transfer in C#. Hope it helps you!