GraphicsPath path = new GraphicsPath();

//添加矩形（正方形）
Rectangle rect = new Rectangle(50, 50, 100, 100);
path.AddRectangle(rect);
//添加橢圓（圓形）
Rectangle ellipseRect = new Rectangle(50, 50, 100, 100);
path.AddEllipse(ellipseRect);
//添加多邊形（三角形為例）
PointF[] trianglePoints = {
    new PointF(100, 50),
    new PointF(150, 150),
    new PointF(50, 150)
};
path.AddPolygon(trianglePoints);
//添加線條（線段）
PointF start = new PointF(50, 50);
PointF end = new PointF(150, 150);
path.AddLine(start, end);
//添加閉合路徑（例如箭頭）
PointF[] arrowPoints = {
    new PointF(100, 50),
    new PointF(150, 100),
    new PointF(130, 100),
    new PointF(130, 150),
    new PointF(70, 150),
    new PointF(70, 100),
    new PointF(50, 100),
    new PointF(100, 50)
};
path.AddPolygon(arrowPoints);
path.CloseFigure(); // 確保閉合

private void panel1_MouseMove(object sender, MouseEventArgs e)
{
    PointF mousePoint = new PointF(e.X, e.Y);
    if (path.IsVisible(mousePoint))
    {
        Console.WriteLine("鼠標在圖形內(nèi)部");
    }
    if (path.IsOutlineVisible(mousePoint, pen))
    {
        Console.WriteLine("鼠標在圖形輪廓線上");
    }
}

Pen pen = new Pen(Color.Black, 2); // 至少寬度為 2 才容易命中

protected override void OnPaint(PaintEventArgs e)
{
    base.OnPaint(e);
    e.Graphics.DrawPath(Pens.Red, path); // 繪制路徑輪廓
    e.Graphics.FillPath(Brushes.LightBlue, path); // 填充路徑
}

public bool IsMouseNearLine(PointF p1, PointF p2, PointF mouse, float tolerance = 5f)
{
    float distance = DistanceFromPointToLine(p1, p2, mouse);
    return distance <= tolerance;
}
private float DistanceFromPointToLine(PointF a, PointF b, PointF p)
{
    float length = (float)Math.Sqrt((b.X - a.X) * (b.X - a.X) + (b.Y - a.Y) * (b.Y - a.Y));
    if (length == 0) return (float)Math.Sqrt((p.X - a.X) * (p.X - a.X) + (p.Y - a.Y) * (p.Y - a.Y));
    float t = ((p.X - a.X) * (b.X - a.X) + (p.Y - a.Y) * (b.Y - a.Y)) / (length * length);
    t = Math.Max(0, Math.Min(1, t));
    float projectionX = a.X + t * (b.X - a.X);
    float projectionY = a.Y + t * (b.Y - a.Y);
    return (float)Math.Sqrt((p.X - projectionX) * (p.X - projectionX) + (p.Y - projectionY) * (p.Y - projectionY));
}

path.Reset(); // 清空路徑
path.Dispose(); // 釋放資源（記得在不再需要時調(diào)用）