#region

using System.Drawing;
using System.Windows.Forms;

#endregion

namespace CSFramework.Library.CommonClass
{
    /// <summary>
    ///     拖动鼠标移动窗体Form通用类
    /// </summary>
    public class FormDragDrop
    {
        private Form _form;
        private bool _IsMouseDown;
        private Point _MouseOffset;

        private FormDragDrop(Form form)
        {
            _form = form;
        }

        /// <summary>
        ///     使用方法
        /// </summary>
        /// <param name="form"></param>
        public static void Handle(Form form)
        {
            var F = new FormDragDrop(form);
            F.HandleEvents();
        }

        private void HandleEvents()
        {
            _form.MouseDown += On_MouseDown;
            _form.MouseMove += On_MouseMove;
            _form.MouseUp += On_MouseUp;
        }

        private void On_MouseDown(object sender, MouseEventArgs e)
        {
            int xOffset;
            int yOffset;

            if (e.Button == MouseButtons.Left)
            {
                xOffset = -e.X;
                yOffset = -e.Y;
                _MouseOffset = new Point(xOffset, yOffset);
                _IsMouseDown = true;
            }
        }

        private void On_MouseMove(object sender, MouseEventArgs e)
        {
            if (_IsMouseDown)
            {
                var mousePos = Control.MousePosition;
                mousePos.Offset(_MouseOffset.X, _MouseOffset.Y);
                _form.Location = mousePos;
            }
        }

        private void On_MouseUp(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left) _IsMouseDown = false;
        }
    }
}