C＃：Windows应用程序读取CSV文件并写入控制台问题

Question

I have a Windows Forms app that is able to launch a console for debuggin. In the app, through a menu click, I read a CSV file and write it to the console. The function that does this is below.

    protected void menuRead_Click(object sender, EventArgs e)
    {
        // ... functionality to load CSV files
        System.IO.Stream inputDataFile = null;
        OpenFileDialog fd = new OpenFileDialog();
        fd.InitialDirectory = "c:\\";
        fd.Filter = "csv files (*.csv)|*.csv|All files (*.*)|*.*";
        fd.FilterIndex = 1;
        fd.RestoreDirectory = true;
        if (fd.ShowDialog() == DialogResult.OK)
        {
            try
            {
                if ((inputDataFile = fd.OpenFile()) != null)
                {
                    inputData_exists = true;
                    // ... read input data from CSV file
                    using (CsvFileReader reader = new CsvFileReader(inputDataFile))
                    {
                        CsvRow row = new CsvRow();
                        while (reader.ReadRow(row))
                        {
                            foreach (string s in row)
                            {
                                Console.Write(s);
                                Console.Write(" ");
                            }
                            Console.WriteLine();
                        }

                        // ... close the input data stream
                        inputDataFile.Close();
                    }
                }
            }
            catch (Exception err)
            {
                //Inform the user if can't read the file
                MessageBox.Show(err.Message);
            }
        }
    }

Everything works fine except the following: The csv file has about 1200 lines of code. When this code is executed, the OpenFileDialog() window only closes partially before the csv file contents begin to get written to the console window. So, I can see the data writing to the console window, and I have a small rectangular portion of the dialog window showing on my form. Is there any way to ensure the dialog is closed before the data is written to the console? Should I open anew thread to communicate with the console? Any advise or help woulf be greatly appreciated. Thank you.

Answer 1

Your issue comes from the fact you display the console and your ShowDialog call. Get the result of the of Dialog then open your console application. You can also read the file on another thread I suppose.

Answer 2

You may use a lot of approaches here. The simplest one: Use StringBuilder and than put all data at once. Because output to console may be quite slowly.

StringBuilder consoleBuffer = new StringBuilder();
using (CsvFileReader reader = new CsvFileReader(inputDataFile))
{
    CsvRow row = new CsvRow();
    while (reader.ReadRow(row))
    {
        foreach (string s in row)
        {
            consoleBuffer.Append(s);
            consoleBuffer.Append(" ");
        }
        consoleBuffer.Append(Environment.NewLine);
    }

    Console.WriteLine(consoleBuffer.ToString());

    // ... close the input data stream
    inputDataFile.Close();
}

Answer 3

You need to give some time for your control "OpenFileDialog" to repaint itself during dispose of the control, the easiest way for WinForm is to use Application.DoEvents()

if (fd.ShowDialog() == DialogResult.OK)
{      
    Application.DoEvents();
    ...
    ...
}