How to properly split a CSV using C# split() function?

Question

Suppose I have this CSV file :

NAME,ADDRESS,DATE
"Eko S. Wibowo", "Tamanan, Banguntapan, Bantul, DIY", "6/27/1979"

I would like like to store each token that enclosed using a double quotes to be in an array, is there a safe to do this instead of using the String split() function? Currently I load up the file in a RichTextBox, and then using its Lines[] property, I do a loop for each Lines[] element and doing this :

string[] line = s.Split(',');

s is a reference to RichTextBox.Lines[]. And as you can clearly see, the comma inside a token can easily messed up split() function. So, instead of ended with three token as I want it, I ended with 6 tokens

Any help will be appreciated!

Answer 1

You could use regex too:

string input = "\"Eko S. Wibowo\", \"Tamanan, Banguntapan, Bantul, DIY\", \"6/27/1979\"";
string pattern = @"""\s*,\s*""";

// input.Substring(1, input.Length - 2) removes the first and last " from the string
string[] tokens = System.Text.RegularExpressions.Regex.Split(
    input.Substring(1, input.Length - 2), pattern);

This will give you:

Eko S. Wibowo
Tamanan, Banguntapan, Bantul, DIY
6/27/1979

Answer 2

I've done this with my own method. It simply counts the amout of " and ' characters.
Improve this to your needs.

    public List<string> SplitCsvLine(string s) {
        int i;
        int a = 0;
        int count = 0;
        List<string> str = new List<string>();
        for (i = 0; i < s.Length; i++) {
            switch (s[i]) {
                case ',':
                    if ((count & 1) == 0) {
                        str.Add(s.Substring(a, i - a));
                        a = i + 1;
                    }
                    break;
                case '"':
                case '\'': count++; break;
            }
        }
        str.Add(s.Substring(a));
        return str;
    }