C# How to make application continue running even after application file is deleted

Question

Is it possible to make it so that even after the application file is removed, the application once executed, will still continue running until the end?

I have a portable Console Application that runs on a removable drive and would like it to continue running even if the drive is accidentally removed, is that possible?

I saw http://www.codeproject.com/Articles/13897/Load-an-EXE-File-and-Run-It-from-Memory but it does not seem to work.

Answer 1

If your console application has some referenced assemblies then they might not be loaded until they are used.

You have to load all related assemblies in your main method or somewhere in the bootstrapper/startup:

var loadedAssemblies = AppDomain.CurrentDomain.GetAssemblies().ToList();
var loadedPaths = loadedAssemblies.Select(a => a.Location).ToArray();

var referencedPaths = Directory.GetFiles(AppDomain.CurrentDomain.BaseDirectory, "*.dll");
var toLoad = referencedPaths.Where(r => !loadedPaths.Contains(r, StringComparer.InvariantCultureIgnoreCase)).ToList();
toLoad.ForEach(path => loadedAssemblies.Add(AppDomain.CurrentDomain.Load(AssemblyName.GetAssemblyName(path))));

Answer 2

The problem with the approach in the article (from your perspective) is that you need to launch it from another application, and that application's binary must be present at all times, so you can't launch that one from the same location, or you haven't got rid of the problem.

One mechanism could be:

1. User starts app
2. App copies itself to the temp folder.
3. App launches the temp copy using Process.Start and a /nocopy parameter
4. App closes itself.
5. Temp app starts up, reads the /nocopy parameter and skips the copy and launches.

Answer 3

The comment by ElmoDev001 led me to achieve the results I wanted.

There are errors but here is the general idea:

Program.cs (Main class)

class Program    {
    static void Main(string[] args)
    {
        String Temp = System.IO.Path.GetTempPath();
        String tmpDir = Temp + @"tmp\";

        String fileName = String.Concat(Process.GetCurrentProcess().ProcessName, ".exe");
        String filePath = Path.Combine(Extension.AssemblyDirectory, fileName);
        String tempFilePath = Path.Combine(tmpDir, fileName);

        if (!Directory.Exists(tmpDir)) { Directory.CreateDirectory(tmpDir); }

        if (!(string.Equals(filePath, tempFilePath))) // if the application is not running at temp folder
        {
            if (!(File.Exists(tempFilePath))) // if the application does not exist at temp folder
            {
                ext.initFile();
            }
            else if (File.Exists(tempFilePath)) // if the application already exists at temp folder
            {
                File.Delete(tempFilePath);
                ext.initFile();
            }
        }
        else if (string.Equals(filePath, tempFilePath)) // if the application is running at temp folder
        {
                //main code
        }
    }
}

Extension.cs

class Extension
{

    String Temp = System.IO.Path.GetTempPath();
    String tmpDir = Temp + @"tmp\";

    String fileName = String.Concat(Process.GetCurrentProcess().ProcessName, ".exe");
    String filePath = Path.Combine(Extension.AssemblyDirectory, fileName);
    String tempFilePath = Path.Combine(tmpDir, fileName);

    public static string AssemblyDirectory
    {
        get
        {
            string codeBase = Assembly.GetExecutingAssembly().CodeBase;
            UriBuilder uri = new UriBuilder(codeBase);
            string path = Uri.UnescapeDataString(uri.Path);
            return Path.GetDirectoryName(path);
        }
    }

    public static void initFile()
    {
            File.Copy(filePath, tempFilePath);
            Process.Start(tempFilePath);
            System.Environment.Exit(0);
    }
 }