DownloadSFTPFileCmdlet.cs

using Renci.SshNet;
using System;
using System.Collections.Generic;
using System.Management.Automation;
using System.Text;
 
namespace SFTPSyncer
{
    [Cmdlet("Download", "SFTPFile")]
    public class DownloadSFTPFileCmdlet : Cmdlet
    {
        [Parameter(Position = 0, Mandatory = true)]
        [ValidateNotNullOrEmpty()]
        public SftpClient Connection { get; set; }
 
 
        [Parameter(Position = 1, Mandatory = true)]
        public string Filename { get; set; }
 
        [Parameter(Position = 2, Mandatory = true)]
        public string Target { get; set; }
 
        protected override void ProcessRecord()
        {
            base.ProcessRecord();
            System.IO.Stream targetStream = null;
            try
            {
                if (System.IO.File.GetAttributes(Target).HasFlag(System.IO.FileAttributes.Directory))
                {
                    var fn = System.IO.Path.GetFileName(Filename);
                    var targetFile = System.IO.Path.Combine(Target, fn);
                    targetStream = System.IO.File.Create(targetFile);
                }
                else
                {
                    targetStream = System.IO.File.Create(Target);
                }
                Connection.DownloadFile(Filename, targetStream);
            }
            finally
            {
                targetStream?.Dispose();
            }
        }
    }
}