.NET (Core and Framework)

public partial class TextFieldParser
{
    public TextFieldParser()
    {
    }

    public string[] ParseFields(string text)
    {
        string[] parts = text.Split(',');

        List<string> newParts = new List<string>();
        bool inQuotes = false;
        string currentPart = string.Empty;

        for (int i = 0; i < parts.Length; i++) 
        {
            string part = parts[i];
            inQuotes = (inQuotes || part.StartsWith("\""));
            if (inQuotes)
            {
                currentPart = (string.IsNullOrEmpty(currentPart))? part : string.Format("{0},{1}", currentPart, part);
            }
            else
            {
                currentPart = part;
            }
            inQuotes = (inQuotes && !part.EndsWith("\""));
            if (!inQuotes)
            {
                currentPart = currentPart.Replace("\"", "");
                newParts.Add(currentPart);
                currentPart = string.Empty;
            }
        }

        return newParts.ToArray();
    }
}