Form1.cs

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;
using System.Globalization;

namespace P2_to_P3
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void openFileDialog1_FileOk(object sender, CancelEventArgs e)
        {

        }

        private void button1_Click(object sender, EventArgs e)
        {
            if (openFileDialog1.ShowDialog() == DialogResult.OK)
            {
                textBox1.Text = openFileDialog1.FileName;
            }
        }

        private void button2_Click(object sender, EventArgs e)
        {
            bool debug = false; //Ignore file already converted.
            string csv = File.ReadAllText(textBox1.Text);
            if (debug == !true)
            {
                if (!csv.Contains("P-GPS"))
                {
                    csv = csv.Replace("GPS", "P-GPS");
                }
                else
                {
                    MessageBox.Show("This log has already been converted");
                    goto End;
                }
            }
            else
            {
                csv = csv.Replace("GPS", "P-GPS");
            }

            File.WriteAllText(textBox1.Text, csv);
            Chilkat.Csv chcsv = new Chilkat.Csv();

            bool load = chcsv.LoadFile(textBox1.Text);
            if (load = !true)
            {
                MessageBox.Show("load failed!");
            }
            int lineCount = File.ReadLines(textBox1.Text).Count();
            MessageBox.Show("There are " + lineCount + " lines");
            progressBar1.Maximum = lineCount;
            for (int i = 1; i <= lineCount-1; i++)
            {
                bool setcelltest = chcsv.SetCell(i, 50, "4");
                string gettemp = chcsv.GetCell(i, 33);
                string tempout = gettemp.Replace(',', '.');
                double tempoutout = double.Parse(tempout, CultureInfo.InvariantCulture);
                double kelvintemp = tempoutout*10 + 2732;
                double kelvindone = kelvintemp - 0.5;
                string kelvinstring = Convert.ToString(kelvindone);
                string kelvincomplete = kelvinstring.Replace(",", ".");
                bool settemptest = chcsv.SetCell(i, 33, kelvincomplete);
                progressBar1.Value = i;
            }
            chcsv.SetCell(1, 52, textBox2.Text);
            MessageBox.Show("Done converting! Upload to HealthyDrones and enjoy!");
            bool savetest = chcsv.SaveFile(textBox1.Text);
        End:;
        }
    }
}