How to read csv using LINQ ,some columns contain , - linq

Question

i have a CSV in the below way. "India,Inc" is a company name which is single value which contains , in it
How to Get the Values in LINQ
12321,32432,423423,Kevin O'Brien,"India,Inc",234235,23523452,235235

Answer 1

Assuming that you will always have the columns that you specify and that the only variable is that company name can have commas inside, this UGLY code can help you achieve your goal.
var file = File.ReadLines("test.csv");
var value = from p in file
select new string[]
{ p.Split(',')[0],
p.Split(',')[1],
p.Split(',')[2],
p.Split(',')[3],
p.Split(',').Count() == 7 ? p.Split(',')[4] :
(p.Split(',').Count() > 7 ? String.Join(",",p.Split(',').Skip(4).Take(p.Split(',').Count() - 7).ToArray() ) : ""),
p.Split(',')[p.Split(',').Count() - 3],
p.Split(',')[p.Split(',').Count() - 2],
p.Split(',')[p.Split(',').Count() - 1]
};

Answer 2

A regular expression would work, bit nasty due to the recursive nature but it does achieve your goal.
List<string> matches = new List<string>();
string subjectString = "12321,32432,423423,Kevin O'Brien,\"India,Inc\",234235,23523452,235235";
Regex regexObj = new Regex(#"(?<="")\b[123456789a-z,']+\b(?="")|[123456789a-z']+", RegexOptions.IgnoreCase);
Match matchResults = regexObj.Match(subjectString);
while (matchResults.Success)
{
matches.Add(matchResults.Value);
// matched text: matchResults.Value
// match start: matchResults.Index
// match length: matchResults.Length
matchResults = matchResults.NextMatch();
}

Answer 3

This should suffice in most cases. It handles quoted strings, strings with double quotes within them, and embedded commas.
var subjectString = "12321,32432,423423,Kevin O'Brien,\"India,Inc\",234235,\"Test End\"\"\",\"\"\"Test Start\",\"Test\"\"Middle\",23523452,235235";
var result=Regex.Split(subjectString,#",(?=(?:[^""]*""[^""]*"")*[^""]*$)")
.Select(x=>x.StartsWith("\"") && x.EndsWith("\"")?x.Substring(1,x.Length-2):x)
.Select(x=>x.Replace("\"\"","\""));
It does however break, if you have a field with a single double quote inside it, and the string itself is not enclosed in double quotes -- this is invalid in most definitions of a CSV file, where any field that contains CR, LF, Comma, or Double quote must be enclosed in double quotes.
You should be able to reuse the same Regex expression to break on lines as well for small CSV files. Larger ones you would want a better implementation. Replace the double quotes with LF, and remove the matching ones (unquoted LF's). Then use the regular expression again replacing the quotes with CR, and split on matching.

Answer 4

Another option is to use CSVHelper and not traying to reinvent the wheel
var csv = new CsvHelper.CsvReader(new StreamReader("test.csv"));
while (csv.Read())
{
Console.WriteLine(csv.GetField<int>(0));
Console.WriteLine(csv.GetField<string>(1));
Console.WriteLine(csv.GetField<string>(2));
Console.WriteLine(csv.GetField<string>(3));
Console.WriteLine(csv.GetField<string>(4));
}
Guide

Answer 5

I would recommend LINQ to CSV, because it is powerful enough to handle special characters including commas, quotes, and decimals. They have really worked a lot of these issues out for you.
It only takes a few minutes to set up and it is really worth the time because you won't run into these types of issues down the road like you would with custom code. Here are the basic steps, but definitely follow the instructions in the link above.
Install the Nuget package
Create a class to represent a line item (name the fields the way they're named in the csv)
Use CsvContext.Read() to read into an IEnumerable which you can easily manipulate with LINQ
Use CsvContext.Write() to write a List or IEnumerable to a CSV
This is very easy to setup, has very little code, and is much more scalable than doing it yourself.

Answer 6

becuase you're only reading values delminated bycommas, the spaces shouldn't cause an issue if you just treat them like any other character.
var values = File.ReadLines(path)
SelectMany(line => line.Split(','));