Saving contents of listview as a CSV File in c#

Question

I have a standalone c# App with a listview that display data read by my program. I am saving it as an excel file it works great , but the data when saved is dumped all in column, I have tried saving it as csv file ,but I cant get it to do what I want let each distinct be on a separate column please any heads up would highly welcome This is how my output is designed and I want that each should be on a separate column when I open the excel file.

   listView1.Items.Add(vis.brand+ "," + (vis.Count) + ","vis.model + "," + Math.Round(vis.sum));

Answer 1

You could use this example, choose the C# version.

It should do exactly what you want to achieve. This function should do the trick:

    private void Button1_Click(object sender, EventArgs e)
    {
        //declare new SaveFileDialog + set it's initial properties
            SaveFileDialog sfd = new SaveFileDialog {
                Title = "Choose file to save to",
                FileName = "example.csv",
                Filter = "CSV (*.csv)|*.csv",
                FilterIndex = 0,
                InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments)
            };

            //show the dialog + display the results in a msgbox unless cancelled

            if (sfd.ShowDialog() == DialogResult.OK) {

                string[] headers = ListView1.Columns
                           .OfType<ColumnHeader>()
                           .Select(header => header.Text.Trim())
                           .ToArray();

                string[][] items = ListView1.Items
                            .OfType<ListViewItem>()
                            .Select(lvi => lvi.SubItems
                                .OfType<ListViewItem.ListViewSubItem>()
                                .Select(si => si.Text).ToArray()).ToArray();

                string table = string.Join(",", headers) + Environment.NewLine;
                foreach (string[] a in items)
                {
                    //a = a_loopVariable;
                    table += string.Join(",", a) + Environment.NewLine;
                }
                table = table.TrimEnd('\r', '\n');
                System.IO.File.WriteAllText(sfd.FileName, table);
            }
    }

Answer 2

The answer by @McRonald mostly covers it, but will fail for important edge cases.

If you have a comma or quote in any string, it will mess up the output. For example if you had a CSV with columns LastName and FirstName, someone with a suffix like ", Jr" would throw off the commas:

LastName, FirstName
Smith, John
Baker, Jr, Fred

I developed an extension method that applies any necessary escaping to a string that is being written to a cell of a CSV file (the code could be shortened, but is easiest to follow as written):

static public class CsvExtensions
{
    static public string CsvQuote(this string text)
    {
        if (text == null)
        {
            return string.Empty;
        }

        bool containsQuote = false;
        bool containsComma = false;
        bool containsNewline = false;
        bool containsCR = false;
        int len = text.Length;
        for (int i = 0; i < len && (containsComma == false || containsQuote == false); i++)
        {
            char ch = text[i];
            if (ch == '"')
            {
                containsQuote = true;
            }
            else if (ch == ',')
            {
                containsComma = true;
            }
            else if (ch == '\r')
            {
                containsCR = true;
            }
            else if (ch == '\n')
            {
                containsNewline = true;
            }
        }

        bool mustQuote = containsComma || containsQuote || containsCR || containsNewline;

        if (containsQuote)
        {
            text = text.Replace("\"", "\"\"");
        }

        if (mustQuote)
        {
            return "\"" + text + "\"";  // Quote the cell and replace embedded quotes with double-quote
        }
        else
        {
            return text;
        }
    }

}

You would place all of that code in it's own class, then use it like this (taking a line of code from @McRonald's answer):

table += string.Join(",", a) + Environment.NewLine;

becomes

table += string.Join(",", a.CsvQuote()) + Environment.NewLine;