UI

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;

namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        string directory;
        string[] files;

        public Form1()
        {
            InitializeComponent();
        }

        private void pictureBox1_Click(object sender, EventArgs e)
        {
            MouseEventArgs me = (MouseEventArgs)e;
            Point coordinates = me.Location;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            FolderBrowserDialog openFolder = new FolderBrowserDialog();

            if (openFolder.ShowDialog() == DialogResult.OK)
            {
                directory = openFolder.SelectedPath;
            }
        }
    }
}