FIXED

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Globalization;

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


        //
        // THIS IS WHERE MY CODE BEGINS
        //

        // indicate whether we are currently converting anything
        bool converting = false;

        // This helper method gets a float from a text box
        double get(TextBox textbox)
        {
            try
            {
                // InvariantCulture always wants . for decimal point
                string value = textbox.Text.Replace(",", ".");

                return double.Parse(
                    value,
                    NumberStyles.Float,
                    CultureInfo.InvariantCulture);
            }
            catch
            {
                return 0;
            }
        }

        // This helper method displays a float in a text box
        void show(TextBox textbox, double value)
        {
            textbox.Text = Math.Round(value, 2).ToString();
        }



        //
        // The remaining two methods are triggered when a text box is modified
        //

        // Triggered whenever an imperial text box is edited
        void toMetric(object sender, EventArgs e)
        {
            // do not continue if we're already doing a conversion
            if (converting) return;
            converting = true;

            // get the feet and inches from the gui
            double inches = 12 * get(_feet) + get(_inch);

            // convert to centimeters and meters
            double centis = inches * 2.54;
            double meters = centis / 100;
            centis %= 100;

            // show conversion results in the gui
            show(_meter, (int)meters);
            show(_centi, centis);

            // conversion has finished, safe to re-enable signals
            converting = false;
        }

        // Triggered whenever a metric text box is edited
        private void toImperial(object sender, EventArgs e)
        {
            // do not continue if we're already doing a conversion
            if (converting) return;
            converting = true;

            // Get values from imerpail text boxes
            double centis = 100 * get(_meter) + get(_centi);

            // Conversions
            double inches = centis / 2.54;
            double feet = inches / 12;
            inches %= 12;

            // show conversion results in the gui
            show(_feet, (int)feet);
            show(_inch, inches);

            // can now do additional conversions
            converting = false;
        }
    }
}