Comma seperated textbox value to list/array of strings - Is there a better way to write this code?

Question

I want to create an array/list of strings of the Comma seperated strings (file extensions) that are entered in a Textbox.

For the following block of code:

            Dim csv As String = Textbox1.Text + ","

            While csv.IndexOf(".") <> -1
                lstOfStrings.Add(csv.Substring(0, csv.IndexOf(",")))
                csv = csv.Remove(0, csv.IndexOf(",") + 1)
            End While

The output is:

Textbox1.Text = ".exe,.php"

listOfStrings = { ".exe", ".php" }

Is there a better way to write this code?

Answer 1

A better way would be to use the Split method:

Dim lstOfStrings() As String = Textbox1.Text.Split(","c)

Answer 2

Here is a different way with Regex+LINQ. It allows for whole file names, if thats something you value. Split is preferable depending on how conditioned the input is (spaces and the like).

using System;
using System.Linq;
using System.Text.RegularExpressions;
using System.Collections.Generic;

namespace ConsoleApplication2
{
    class Program
    {
        static void Main(string[] args)
        {
            string s = "fileone.aspx, filetwo.csv,filethree.exe, filefour.php";
            List<string> extensions = Regex.Matches(s, @"(\.\w+)\s*,?")
                .OfType<Match>().Select(m => m.Groups[1].Value)
                .ToList();
            extensions.ForEach(i => Console.WriteLine(i));
            Console.ReadLine();
        }
    }
}

OUTPUT

.aspx

.csv

.exe

AFTERTHOUGHT

You could add .Distinct() if you wanted unique extensions