asp.net Convert CSV string to string[]

Question

Is there an easy way to convert a string from csv format into a string[] or list?

I can guarantee that there are no commas in the data.

Answer 1

CsvString.split(',');

Answer 2

string[] splitString = origString.Split(',');

(Following comment not added by original answerer) Please keep in mind that this answer addresses the SPECIFIC case where there are guaranteed to be NO commas in the data.

Answer 3

Get a string[] of all the lines:

string[] lines = System.IO.File.ReadAllLines("yourfile.csv");

Then loop through and split those lines (this error prone because it doesn't check for commas in quote-delimited fields):

foreach (string line in lines)
{
    string[] items = line.Split({','}};
}

Answer 4

string test = "one,two,three";

string[] okNow = test.Split(',');

Answer 5

string s = "1,2,3,4,5";

string myStrings[] = s.Split({','}};

Note that Split() takes an array of characters to split on.

Answer 6

separationChar[] = {';'}; // or '\t' ',' etc.

var strArray = strCSV.Split(separationChar);

Answer 7

string[] splitStrings = myCsv.Split(",".ToCharArray());

Answer 8

If you want robust CSV handling, check out FileHelpers

Answer 9

There isn't a simple way to do this well, if you want to account for quoted elements with embedded commas, especially if they are mixed with non-quoted fields.

You will also probably want to convert the lines to a dictionary, keyed by the column name.

My code to do this is several hundred lines long.

I think there are some examples on the web, open source projects, etc.

Answer 10

Try:

Regex rex = new Regex(",(?=([^\"]*\"[^\"]*\")*(?![^\"]*\"))");
string[] values = rex.Split( csvLine );

Source: http://weblogs.asp.net/prieck/archive/2004/01/16/59457.aspx

Answer 11

Some CSV files have double quotes around the values along with a comma. Therefore sometimes you can split on this string literal: ","

Answer 12

A Csv file with Quoted fields, is not a Csv file. Far more things (Excel) output without quotes rather than with quotes when you select "Csv" in a save as.

If you want one you can use, free, or commit to, here's mine that also does IDataReader/Record. It also uses DataTable to define/convert/enforce columns and DbNull.

http://github.com/claco/csvdatareader/

It doesn't do quotes.. yet. I just tossed it together a few days ago to scratch an itch.

Forgotten Semicolon: Nice link. Thanks. cfeduke: Thanks for the tip to Microsoft.VisualBasic.FileIO.TextFieldParser. Going into CsvDataReader tonight.

Answer 13

String.Split is just not going to cut it, but a Regex.Split may - Try this one:

using System.Text.RegularExpressions;

string[] line;
line = Regex.Split( input, ",(?=(?:[^\"]*\"[^\"]*\")*(?![^\"]*\"))");

Where 'input' is the csv line. This will handle quoted delimiters, and should give you back an array of strings representing each field in the line.

Answer 14

You can take a look at using the Microsoft.VisualBasic assembly with the

Microsoft.VisualBasic.FileIO.TextFieldParser

It handles CSV (or any delimiter) with quotes. I've found it quite handy recently.

Answer 15

Try this;

static IEnumerable<string> CsvParse(string input)
{
 // null strings return a one-element enumeration containing null.
 if (input == null)
 {
  yield return null;
  yield break;
 }

 // we will 'eat' bits of the string until it's gone.
 String remaining = input;
 while (remaining.Length > 0)
 {

  if (remaining.StartsWith("\"")) // deal with quotes
  {
   remaining = remaining.Substring(1); // pass over the initial quote.

   // find the end quote.
   int endQuotePosition = remaining.IndexOf("\"");
   switch (endQuotePosition)
   {
    case -1:
     // unclosed quote.
     throw new ArgumentOutOfRangeException("Unclosed quote");
    case 0:
     // the empty quote
     yield return "";
     remaining = remaining.Substring(2);
     break;
    default:
     string quote = remaining.Substring(0, endQuotePosition).Trim();
     remaining = remaining.Substring(endQuotePosition + 1);
     yield return quote;
     break;
   }
  }
  else // deal with commas
  {
   int nextComma = remaining.IndexOf(",");
   switch (nextComma)
   {
    case -1:
     // no more commas -- read to end
     yield return remaining.Trim();
     yield break;

    case 0:
     // the empty cell
     yield return "";
     remaining = remaining.Substring(1);
     break;

    default:
     // get everything until next comma
     string cell = remaining.Substring(0, nextComma).Trim();
     remaining = remaining.Substring(nextComma + 1);
     yield return cell;
     break;
   }
  }
 }

}

Answer 16

http://github.com/claco/csvdatareader/ updated using TextFieldParser suggested by cfeduke.

Just a few props away from exposing separators/trimspaces/type ig you just need code to steal.

Answer 17

I was already splitting on tabs so this did the trick for me:

public static string CsvToTabDelimited(string line) {
    var ret = new StringBuilder(line.Length);
    bool inQuotes = false;
    for (int idx = 0; idx < line.Length; idx++) {
     if (line[idx] == '"') {
      inQuotes = !inQuotes;
     } else {
      if (line[idx] == ',') {
       ret.Append(inQuotes ? ',' : '\t');
      } else {
       ret.Append(line[idx]);
      }
     }
    }
    return ret.ToString();
}