C# 飄動視窗實作：雙 Timer 控制水平往返移動與邊界檢測

核心原理

使用兩個 Timer 控制視窗水平往返移動：

• timer1：向右移動 (X + 1)，到達右邊界啟動 timer2
• timer2：向左移動 (X - 1)，到達左邊界啟動 timer1

完整程式碼

public partial class Form1 : Form
{
    private void Form1_Load(object sender, EventArgs e)
    {
        this.DesktopLocation = new Point(0, 240);  // 初始位置
    }

    private void timer1_Tick(object sender, EventArgs e)  // 向右
    {
        Point p = new Point(this.DesktopLocation.X + 1, this.DesktopLocation.Y);
        this.DesktopLocation = p;
        
        if (p.X == 630)  // 右邊界
        {
            timer1.Enabled = false;
            timer2.Enabled = true;
        }
    }

    private void timer2_Tick(object sender, EventArgs e)  // 向左
    {
        Point p = new Point(this.DesktopLocation.X - 1, this.DesktopLocation.Y);
        this.DesktopLocation = p;
        
        if (p.X == 20)  // 左邊界
        {
            timer1.Enabled = true;
            timer2.Enabled = false;
        }
    }

    private void button1_Click(object sender, EventArgs e)
    {
        timer1.Stop();
        timer2.Stop();
    }
}

延伸應用

效能與體驗考量

• Timer.Interval = 10-20ms 可獲得較平滑動畫
• 頻繁修改 DesktopLocation 會觸發重繪，複雜視窗可能閃爍
• 建議啟用 DoubleBuffered = true 減少閃爍
• 現代專案考慮 WPF Animation 或 WinForms AnimateWindow API