New to C# - working with dialog boxes and loops

Hello,

I am literally brand new to C# (I generally use PowerShell), and I am working on some web development in Visual Studio. I have a PS script that when a user runs it, it opens a file dialog box prompting for a text file, then takes that text file (which is a list of machine names) and iterates through each machine name in the text file, doing some "stuff" to it. So, everything I am finding on this shows that I would be defining a class for OpenFileDialog, etc. - where I am running into confusion is that I am doing this within a controller (.cs) where I already have classes defined, and I am not sure how to just "inject" this file dialog portion into it. It seems no matter where I add it, it is causing confusion - or it could just be that I have no idea what I am doing, and I am not afraid to admit that. I am not looking for "here is your answer", I am really just looking for some information and possibly a nudge in the right direction, etc.

Here is my code. with a nice comment showing where and what I am trying to do. Any guidance (not straight out answer, I am trying to learn) would be appreciated.

Thank you.

Code:

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using SupportToolkit.Models;
using SupportToolkit.WindowsAutomationServices;
using NLog;

namespace SupportToolkit.Controllers
{
    public class RemoveTPOSRecordsController : Controller
    {
        private static Logger recordDeletionLogger = LogManager.GetCurrentClassLogger();

        [Authorize(Roles = @"no\NST_RIT_Users,no\NST_STM_Users,no\NST_Admin_Users,no\NST_CORP_Users")]

        // GET: RemoveTPOSRecords
        public ActionResult Index(RemoveTPOSRecordsModel model)
        {
            if (model.TPOSMachineName != null)
            {

            }

            if (ModelState.IsValid)
            {
                if (!(string.IsNullOrEmpty(model.btnDeleteRecord)))
                {
                    InvokeRecordDeletion(model);
                }
            }

            if (ModelState.IsValid)
            {
                if (!(string.IsNullOrEmpty(model.btnUploadFile)))
                {
                    InvokeBulkDeletion(model);
                }
            }
            return View(model);
        }

        [Authorize(Roles = @"no\NST_RIT_Users,no\NST_STM_Users,no\NST_Admin_Users,no\NST_CORP_Users")]
        public string InvokeRecordDeletion(RemoveTPOSRecordsModel model)
        {
            model.Status = "Running Service";
            var windowsAutomationService = new WindowsAutomationServicesClient();
            string shortServiceOutput;

            var serviceAction = "Remove-TPOSRecords";
            var userName = User.Identity.Name;

            string[] recordDeletionArguments = new string[1];
            recordDeletionArguments[0] = model.TPOSMachineName;

            var serviceOutput = windowsAutomationService.RunAutomationService(serviceAction, userName, recordDeletionArguments);

            recordDeletionLogger.Info(userName + " is attempting to remove the record " + model.TPOSMachineName);

            if (serviceOutput.Length >= 7)
            {
                shortServiceOutput = serviceOutput.Substring(0, 7);
                shortServiceOutput = shortServiceOutput.ToLower();
            }
            else
            {
                shortServiceOutput = serviceOutput;
                shortServiceOutput = shortServiceOutput.ToLower();
            }


            if (shortServiceOutput == "success")
            {
                model.Status = "Successfully removed " + model.TPOSMachineName + " from SCCM and AD";
                recordDeletionLogger.Info(userName + " successfully removed " + model.TPOSMachineName + " from SCCM and AD");
                return "Success";
            }
            else if (serviceOutput.Contains("=FailedMACFind"))
            {
                model.Status = "Failure removing " + model.TPOSMachineName + " from SCCM and AD. Machine name " + model.TPOSMachineName + " not found";
                recordDeletionLogger.Info(userName + " failed to remove " + model.TPOSMachineName + " from SCCM and AD. Machine name " + model.TPOSMachineName + " not found");
                return "Failure";
            }
            else if (serviceOutput.Contains("=MultipleEntries"))
            {
                model.Status = "Failure removing " + model.TPOSMachineName + " from SCCM and AD. Multiple entries for " + model.TPOSMachineName + " were found";
                recordDeletionLogger.Info(userName + " failed to remove " + model.TPOSMachineName + " from SCCM and AD. Multiple entries for " + model.TPOSMachineName + " were found");
                return "Failure";
            }
            else
            {
                model.Status = "Failure removing " + model.TPOSMachineName + " from SCCM and AD. Unknown Error";
                recordDeletionLogger.Info(userName + " failed to remove " + model.TPOSMachineName + " from SCCM and AD");
                return "Failure";

            }

        }

    [Authorize(Roles = @"no\NST_RIT_Users,no\NST_STM_Users,no\NST_Admin_Users")]
        public string InvokeBulkDeletion(RemoveTPOSRecordsModel model)
        {

            //somewhere in here is where I would be adding the file dialog/iteration through machine names, I would assume - then the code below is the "stuff" that happens to each machine

            model.Status = "Running Service";
            var windowsAutomationService = new WindowsAutomationServicesClient();
            string shortServiceOutput;

            var registerNames = model.TextMachineName;
            var serviceAction = "Remove-TPOSRecords";
            var userName = User.Identity.Name;

            string[] recordDeletionArguments = new string[1];
            recordDeletionArguments[0] = model.TextMachineName;

            var serviceOutput = windowsAutomationService.RunAutomationService(serviceAction, userName, recordDeletionArguments);

            recordDeletionLogger.Info(userName + " is attempting to remove the record " + model.TextMachineName);

            if (serviceOutput.Length >= 7)
            {
                shortServiceOutput = serviceOutput.Substring(0, 7);
                shortServiceOutput = shortServiceOutput.ToLower();
            }
            else
            {
                shortServiceOutput = serviceOutput;
                shortServiceOutput = shortServiceOutput.ToLower();
            }


            if (shortServiceOutput == "success")
            {
                model.Status = "Successfully removed " + model.TextMachineName + " from SCCM and AD";
                recordDeletionLogger.Info(userName + " successfully removed " + model.TextMachineName + " from SCCM and AD");
                return "Success";
            }
            else if (serviceOutput.Contains("=FailedMACFind"))
            {
                model.Status = "Failure removing " + model.TextMachineName + " from SCCM and AD. Machine name " + model.TextMachineName + " not found";
                recordDeletionLogger.Info(userName + " failed to remove " + model.TextMachineName + " from SCCM and AD. Machine name " + model.TextMachineName + " not found");
                return "Failure";
            }
            else if (serviceOutput.Contains("=MultipleEntries"))
            {
                model.Status = "Failure removing " + model.TextMachineName + " from SCCM and AD. Multiple entries for " + model.TextMachineName + " were found";
                recordDeletionLogger.Info(userName + " failed to remove " + model.TextMachineName + " from SCCM and AD. Multiple entries for " + model.TextMachineName + " were found");
                return "Failure";
            }
            else
            {
                model.Status = "Failure removing " + model.TextMachineName + " from SCCM and AD. Unknown Error";
                recordDeletionLogger.Info(userName + " failed to remove " + model.TextMachineName + " from SCCM and AD");
                return "Failure";

            }

        }

    }

}

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