How do I use DTS.Events.FireInformation() in SSIS Script Task while handling WinSCPnet.dll FileTransferProgress?

问题

I have a Script Task in an SSIS (2008) package that downloads files from a remote FTP server to a local directory. The Script Task is written in C# 2008, and uses WinSCPnet.dll. Using examples from WinSCP's documentation, I came up with the script below. The script functions correctly to download the files, but all the file success/failure messages are held until the entire script completes, and then all the messages are dumped at once. File progress is not displayed at all using Console.Write(), and trying to use Dts.Events.FireInformation() in SessionFileTransferProgress gives me

Error: "An object reference is required for the non-static field, method, or property Microsoft.SqlServer.Dts.Tasks.ScriptTask.VSTARTScriptObjectModelBase.Dts.get"

Is there a way I can use the DTS.events.Fire* events to display file progress information as it happens, and file completion status after each file?

Script:

/*
   Microsoft SQL Server Integration Services Script Task
   Write scripts using Microsoft Visual C# 2008.
   The ScriptMain is the entry point class of the script.
*/

using System;
using Microsoft.SqlServer.Dts.Runtime;
using Microsoft.SqlServer.Dts.Tasks.ScriptTask;
using System.AddIn;
using WinSCP;

namespace ST_3a1cf75114b64e778bd035dd91edb5a1.csproj
{
    [AddIn("ScriptMain", Version = "1.0", Publisher = "", Description = "")]
    public partial class ScriptMain : VSTARTScriptObjectModelBase
    {
        public void Main()
        {
            // Setup session options
            SessionOptions sessionOptions = new SessionOptions
            {
                Protocol = Protocol.Ftp,
                HostName = (string)Dts.Variables["User::FTPServerName"].Value,
                UserName = (string)Dts.Variables["User::UserName"].Value,
                Password = (string)Dts.Variables["User::Password"].Value
            };

            try
            {
                using (Session session = new Session())
                {
                    // Will continuously report progress of transfer
                    session.FileTransferProgress += SessionFileTransferProgress;

                    session.ExecutablePath = (string)Dts.Variables["User::PathToWinSCP"].Value;

                    // Connect
                    session.Open(sessionOptions);

                    TransferOptions transferOptions = new TransferOptions();
                    transferOptions.TransferMode = TransferMode.Binary;


                    TransferOperationResult transferResult = session.GetFiles(
                                                                                (string)Dts.Variables["User::ExportPath"].Value
                                                                                , (string)Dts.Variables["User::ImportPath"].Value
                                                                                , false
                                                                                , transferOptions
                                                                            );

                    // Throw on any error
                    transferResult.Check();

                    // Print results
                    bool fireAgain = false;
                    foreach (TransferEventArgs transfer in transferResult.Transfers)
                    {
                        Dts.Events.FireInformation(0, null,
                            string.Format("Download of {0} succeeded", transfer.FileName),
                            null, 0, ref fireAgain);
                    }
                }

                Dts.TaskResult = (int)DTSExecResult.Success;
            }

            catch (Exception e)
            {
                Dts.Events.FireError(0, null,
                    string.Format("Error downloading file: {0}", e),
                    null, 0);

                Dts.TaskResult = (int)DTSExecResult.Failure;
            }
        }

        private static void SessionFileTransferProgress(object sender, FileTransferProgressEventArgs e)
        {
            //bool fireAgain = false;


            // Print transfer progress
            Console.Write("\r{0} ({1:P0})", e.FileName, e.FileProgress);

            /*Dts.Events.FireInformation(0, null,
                            string.Format("\r{0} ({1:P0})", e.FileName, e.FileProgress),
                            null, 0, ref fireAgain);*/

            // Remember a name of the last file reported
            _lastFileName = e.FileName;
        }

        private static string _lastFileName;
    }
}

回答1:

The answer I figured out was pretty simple. I changed SessionFileTransferProgress from private static void to private void. Once this method was no longer static, I was able to use this to invoke the Dts.Events.Fire* methods. SessionFileTransferProgress was changed to:

private void SessionFileTransferProgress(object sender, FileTransferProgressEventArgs e)
{
    bool fireAgain = false;

    this.Dts.Events.FireInformation(0, null,
                    string.Format("\r{0} ({1:P0})", e.FileName, e.FileProgress),
                    null, 0, ref fireAgain);

    // Remember a name of the last file reported
    _lastFileName = e.FileName;
}

来源：https://stackoverflow.com/questions/51753727/how-do-i-use-dts-events-fireinformation-in-ssis-script-task-while-handling-win