Synchronize Progressbar with Execution of class methods

Question

In my project I have a class that has three methods:

static List<string> ListaArquivos(string path){...}
static void CriaArquivoUnico(List<string> listaArquivos){...}
static void AbreArquivoUnico(string pathArquivoUnico){...}

What I am trying to do is that whenever he enters a method he generates an event saying that he entered that method, so I will update a field with the status of the task, that is, when he enters the Listfiles I update the textbox to "Listing Files", for example. And when I exit the method I need another event warning that it has left the method. How can I create these events ?

Answer 1

The simplest way to do this would be by using BackgroundWorker

Based on your example set up a scenario where will be read the names of the files of a directory, adding each of these files in a list, and for each file read will be updated in a Textbox the percentage of read files, can be updated a ProgressBar in place of TextBox.

    List<string> ListaArquivos(string path)
    {
        List<string> listArquivos = new List<string>();

        BackgroundWorker workerLeituraArquivos = new BackgroundWorker();
        workerLeituraArquivos.WorkerReportsProgress = true;
        workerLeituraArquivos.DoWork += (sender, e) =>
        {
            var arrayArquivos = Directory.GetFiles(path);
            for (int i = 0; i < arrayArquivos.Length; i++)
            {
                listArquivos.Add(arrayArquivos[i]);

                // calculo da porcentagem concluida
                var porcentagem = (100 / arrayArquivos.Length) * (i + 1);
                workerLeituraArquivos.ReportProgress(porcentagem);

                // adicionado apenas para dar tempo de notar a alteração do textbox
                Thread.Sleep(1000); 
            }
        };

        workerLeituraArquivos.ProgressChanged += (sender, e) =>
        {
            txtStatus.Text = string.Format("Listando arquivos. {0}% concluído", e.ProgressPercentage);
        };

        workerLeituraArquivos.RunWorkerCompleted += (sender, e) =>
        {
            txtStatus.Text = "Listagem de arquivos concluída";
        };

        workerLeituraArquivos.RunWorkerAsync();

        return listArquivos;
    }

Another way to be done would be to create a class that extends EventArgsand create a EventHandler, but there would have to be other treatments to be able to update the UI.