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

namespace WindowDragDemo
{
    public partial class Form1 : Form
    {
        // 記錄鼠標(biāo)按下時的起始位置（相對于窗體客戶區(qū)）
        private Point _mouseDownPoint = Point.Empty;

        public Form1()
        {
            InitializeComponent();
            // 可選：隱藏系統(tǒng)標(biāo)題欄（演示無默認(rèn)標(biāo)題欄時的拖動功能）
            this.FormBorderStyle = FormBorderStyle.None;
            this.Size = new Size(800, 600);
            this.StartPosition = FormStartPosition.CenterScreen;
        }

        /// <summary>
        /// 鼠標(biāo)按下時，記錄起始坐標(biāo)
        /// </summary>
        protected override void OnMouseDown(MouseEventArgs e)
        {
            base.OnMouseDown(e); // 保留窗體原有鼠標(biāo)按下邏輯
            // 僅響應(yīng)鼠標(biāo)左鍵操作
            if (e.Button == MouseButtons.Left)
            {
                // 記錄鼠標(biāo)當(dāng)前坐標(biāo)（相對于窗體，而非屏幕）
                _mouseDownPoint = new Point(e.X, e.Y);
            }
        }

        /// <summary>
        /// 鼠標(biāo)移動時，計算并更新窗體位置
        /// </summary>
        protected override void OnMouseMove(MouseEventArgs e)
        {
            base.OnMouseMove(e); // 保留窗體原有鼠標(biāo)移動邏輯
            // 條件：鼠標(biāo)左鍵按住 + 起始坐標(biāo)有效（已記錄）
            if (e.Button == MouseButtons.Left && _mouseDownPoint != Point.Empty)
            {
                // 計算窗體新位置：屏幕坐標(biāo) = 當(dāng)前窗體位置 + 鼠標(biāo)移動偏移量
                this.Location = new Point(
                    this.Left + (e.X - _mouseDownPoint.X), // 水平方向偏移
                    this.Top + (e.Y - _mouseDownPoint.Y)   // 垂直方向偏移
                );
            }
        }

        /// <summary>
        /// 鼠標(biāo)松開時，重置起始坐標(biāo)，結(jié)束拖動
        /// </summary>
        protected override void OnMouseUp(MouseEventArgs e)
        {
            base.OnMouseUp(e); // 保留窗體原有鼠標(biāo)松開邏輯
            // 重置為空，避免后續(xù)無左鍵按下時仍觸發(fā)拖動
            _mouseDownPoint = Point.Empty;
        }
    }
}

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

namespace WindowDragDemo
{
    public partial class Form1 : Form
    {
        // 記錄鼠標(biāo)按下時的起始位置
        private Point _mouseDownPoint = Point.Empty;

        public Form1()
        {
            InitializeComponent();
            // 初始化窗體和自定義標(biāo)題欄
            InitControlSettings();
            // 綁定自定義標(biāo)題欄的鼠標(biāo)事件
            BindTitleBarEvents();
        }

        /// <summary>
        /// 初始化控件設(shè)置
        /// </summary>
        private void InitControlSettings()
        {
            this.FormBorderStyle = FormBorderStyle.None;
            this.Size = new Size(800, 600);
            this.StartPosition = FormStartPosition.CenterScreen;

            // 初始化自定義標(biāo)題欄
            pnlTitleBar.Size = new Size(this.Width, 35);
            pnlTitleBar.Location = new Point(0, 0);
            pnlTitleBar.BackColor = Color.LightSkyBlue;
            pnlTitleBar.BorderStyle = BorderStyle.FixedSingle;
        }

        /// <summary>
        /// 綁定自定義標(biāo)題欄的鼠標(biāo)事件
        /// </summary>
        private void BindTitleBarEvents()
        {
            pnlTitleBar.MouseDown += PnlTitleBar_MouseDown;
            pnlTitleBar.MouseMove += PnlTitleBar_MouseMove;
            pnlTitleBar.MouseUp += PnlTitleBar_MouseUp;
        }

        /// <summary>
        /// 自定義標(biāo)題欄鼠標(biāo)按下事件
        /// </summary>
        private void PnlTitleBar_MouseDown(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)
            {
                _mouseDownPoint = new Point(e.X, e.Y);
            }
        }

        /// <summary>
        /// 自定義標(biāo)題欄鼠標(biāo)移動事件
        /// </summary>
        private void PnlTitleBar_MouseMove(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left && _mouseDownPoint != Point.Empty)
            {
                this.Location = new Point(
                    this.Left + (e.X - _mouseDownPoint.X),
                    this.Top + (e.Y - _mouseDownPoint.Y)
                );
            }
        }

        /// <summary>
        /// 自定義標(biāo)題欄鼠標(biāo)松開事件
        /// </summary>
        private void PnlTitleBar_MouseUp(object sender, MouseEventArgs e)
        {
            _mouseDownPoint = Point.Empty;
        }
    }
}

using System.Windows;
using System.Windows.Input;

namespace WpfWindowDragDemo
{
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
            this.WindowStyle = WindowStyle.None; // 隱藏系統(tǒng)標(biāo)題欄
            this.Width = 800;
            this.Height = 600;
            this.WindowStartupLocation = WindowStartupLocation.CenterScreen;
        }

        /// <summary>
        /// 自定義標(biāo)題欄鼠標(biāo)左鍵按下事件
        /// </summary>
        private void TitleBar_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
        {
            // 調(diào)用WPF內(nèi)置方法，觸發(fā)窗體拖動
            this.DragMove();
        }
    }
}