Editing the contents of an arraylist then writing it to a file c#

Question

I have a .csv file I would like to modify. Here is the format of the file:

Id, UTMGridEast, UTMGridNorth, LocDate, LocTime, Species

This dataset uses UTM coordinates, and I would like to convert them to Latitude/Longitude and place them back into the .csv file in their respective locations. I am able to convert the UTM coordinates already, that part is sorted!

Now, I already have code that seperates these values and adds them to an arraylist. All I need to do now is edit the contents and write it back to the .csv file.

My GUI consists of just two buttons, here is my code so far:

    public partial class MainWindow : Window
{
    private string _filename;

    public MainWindow()
    {
        InitializeComponent();
    }

    private void btnLoad_Click(object sender, RoutedEventArgs e)
    {
        // Configure open file dialog box
        Microsoft.Win32.OpenFileDialog dlg = new Microsoft.Win32.OpenFileDialog();
        dlg.FileName = "Dataset"; // Default file name
        dlg.DefaultExt = ".txt"; // Default file extension
        dlg.Filter = "Commar Seperated Values (.csv)|*.csv" ; // Filter files by extension 

        // Show open file dialog box
        Nullable<bool> result = dlg.ShowDialog();

        // Process open file dialog box results 
        if (result == true)
        {
            // Open document 
            _filename = dlg.FileName;
            txtFilePath.Text = _filename;
        }
    }

    private void btnConvert_Click(object sender, RoutedEventArgs e)
    {
        ConvertToLatLong();
    }

    private void ConvertToLatLong()
    {
        GeoUTMConverter geoUtmConverter = new GeoUTMConverter();
        TextWriter tw = new StreamWriter("starkey.txt");

        string textFile = System.IO.File.ReadAllText(_filename);
        List<string> lines = new List<string>(textFile.Split(new[] { Environment.NewLine }, StringSplitOptions.None));
        for (int iLine = 0; iLine < lines.Count; iLine++)
        {
            List<string> values = new List<string>(lines[iLine].Split(new[] { "," }, StringSplitOptions.None));
            for (int iValue = 0; iValue < values.Count; iValue++)
            {
                Console.WriteLine(String.Format("Line {0} Value {1} : {2}", iLine, iValue, values[iValue]));

                if (iLine > 0)
                {
                    geoUtmConverter.ToLatLon(Convert.ToDouble(values[1]), Convert.ToDouble(values[2]), 11, GeoUTMConverter.Hemisphere.Northern);
                    Double latitude = geoUtmConverter.Latitude;
                    Double longitude = geoUtmConverter.Longitude;
                    Console.WriteLine("Latitude: " + latitude + " Longitude: " + longitude);
                    //EDIT AND WRITE TO FILE HERE 
                }
            }
        }
    }
}

I have tried to create a new arraylist and write that using StreamWriter but I just can't seem to get it correct.

Any help would be GREATLY appreciated, thank you!

Answer 1

The part you seem to be missing is

values[1]=latitude;
values[2]=longitude;
tw.WriteLine(String.Join(",",values);

Dont forget to close writer at the end.