XdCxRhDW/XdCxRhDW.App/ExtensionsDev/ChooseFileExtension.cs

using DevExpress.XtraEditors;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace ExtensionsDev
{
    public static class ChooseFileExtension
    {
        public static ButtonEdit UseChooseFile(this ButtonEdit ctrl,Action<string> onFileChanged=null)
        {
            ctrl.AllowDrop = true;
            ctrl.DragEnter += ctrl_DragEnter;
            ctrl.DragDrop += ctrl_DragDrop;
            ctrl.ButtonClick += Ctrl_ButtonClick;
            ctrl.TextChanged += (sender, e) =>
            {
                string file = (sender as Control).Text;
                if (File.Exists(file))
                {
                    onFileChanged?.Invoke(file);
                }
            };
            return ctrl;
        }

        private static void Ctrl_ButtonClick(object sender, DevExpress.XtraEditors.Controls.ButtonPressedEventArgs e)
        {
            var ctrl = sender as Control;
            XtraOpenFileDialog xtraOpenFileDialog1 = new XtraOpenFileDialog();
            xtraOpenFileDialog1.Multiselect = false;
            var currentDir = Environment.CurrentDirectory;
            if (xtraOpenFileDialog1.ShowDialog() == DialogResult.OK)
            {
                Environment.CurrentDirectory = currentDir;
                ctrl.Text = xtraOpenFileDialog1.FileName;
            }
        }

        private static void ctrl_DragEnter(object sender, DragEventArgs e)
        {
            if (e.Data.GetDataPresent(DataFormats.FileDrop))
            {
                e.Effect = DragDropEffects.Link;
            }
            else
            {
                e.Effect = DragDropEffects.None;
            }
        }

        private static void ctrl_DragDrop(object sender, DragEventArgs e)
        {
            var file = ((Array)e.Data.GetData(DataFormats.FileDrop)).GetValue(0).ToString();
            (sender as Control).Text = file;
        }
    }
}