CSV

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO;

namespace Bankomat
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void openToolStripMenuItem_Click(object sender, EventArgs e)
        {
            string path = "";
            if (openFileDialog1.ShowDialog() == DialogResult.OK)
            {
                try {
                    path = openFileDialog1.FileName;
                    List<string> rows = File.ReadAllLines(path).ToList();
                    DataTable dt = new DataTable();
                    string[] header = rows[0].Split(',');


                foreach (var item in header)
                {
                    dt.Columns.Add(item);
                }
                rows.RemoveAt(0); // удалим Хедер

                string[] fields = null;
                List<string> lstFields;
                string field;

                string tmp;
                foreach (string csvRownt in rows)
                {
                    int InQuote = 0;
                    string csvRow = csvRownt.Trim('\"');//.Replace("\"\"", "\"");
                    lstFields = new List<string>();
                    field = "";
                    for (int i = 0; i < csvRow.Length; i++)
                    {
                        tmp = csvRow.ElementAt(i).ToString();
                        if (tmp == "\"") { InQuote = InQuote + 1; }
                        else
                        {
                            switch (InQuote % 2)
                            {
                                case 1: // в кавычках
                                    {

                                        field += tmp;

                                    }
                                    break;
                                case 0: // не в кавычках
                                    {
                                        if (tmp == ",") { lstFields.Add(field); field = ""; }
                                        else field += tmp;
                                    }
                                    break;
                            }
                        }

                    }
                    if (!string.IsNullOrEmpty(field))
                    {
                        lstFields.Add(field);
                        field = "";
                    }

                    fields = lstFields.ToArray();
                    dt.Rows.Add(fields);

                }

                dataGridView1.DataSource = dt;
                }
                catch (Exception ex) { MessageBox.Show(ex.Message); }
            }
        }
    }
}