c# 自绘图标

//绘制一个下拉菜单按钮
private void drawMenuFlag(int lineWidth, PictureBox picture)
{
    // 创建一个与 PictureBox 大小相同的 Bitmap
    Bitmap bmp = new Bitmap(picture.Width, picture.Height);

    // 创建一个 Graphics 对象，用于在 Bitmap 上绘制图形
    using (Graphics g = Graphics.FromImage(bmp))
    {
        // 启用抗锯齿
        g.SmoothingMode = SmoothingMode.AntiAlias;

        // 设置线条的颜色和宽度
        Pen pen = new Pen(Color.White, lineWidth);

        // 绘制横线
        g.DrawLine(pen, 0, 1, picture.Width, 1);

        // 定义三角形的三个顶点
        Point point1 = new Point(0, 5);
        Point point2 = new Point(picture.Width /2, picture.Height -1);
        Point point3 = new Point(picture.Width, 5);

        // 构建三角形的顶点数组
        Point[] trianglePoints = { point1, point2, point3 };

        // 使用绘图对象绘制三角形
        g.DrawPolygon(pen, trianglePoints);
    }

    // 将绘制好的 Bitmap 显示在 PictureBox 中
    picture.Image = bmp;
}

//绘制关闭按钮
private void drawCloseFlag(int lineWidth, PictureBox picture)
{
    // 创建一个与 PictureBox 大小相同的 Bitmap
    Bitmap bmp = new Bitmap(picture.Width, picture.Height);

    // 创建一个 Graphics 对象，用于在 Bitmap 上绘制图形
    using (Graphics g = Graphics.FromImage(bmp))
    {
        // 启用抗锯齿
        g.SmoothingMode = SmoothingMode.AntiAlias;

        // 设置线条的颜色和宽度
        Pen pen = new Pen(Color.White, lineWidth);

        // 计算叉的四个点
        Point topLeft = new Point(1, 1);
        Point bottomRight = new Point(picture.Width, picture.Height);
        Point topRight = new Point(picture.Width, 0);
        Point bottomLeft = new Point(0, picture.Height);

        // 绘制叉
        g.DrawLine(pen, topLeft, bottomRight);
        g.DrawLine(pen, topRight, bottomLeft);
    }

    // 将绘制好的 Bitmap 显示在 PictureBox 中
    picture.Image = bmp;
}


//绘制最小化按钮
private void drawMinimizeFlag(int lineWidth, PictureBox picture)
{
    // 创建一个与 PictureBox 大小相同的 Bitmap
    Bitmap bmp = new Bitmap(picture.Width, picture.Height);

    // 创建一个 Graphics 对象，用于在 Bitmap 上绘制图形
    using (Graphics g = Graphics.FromImage(bmp))
    {
        // 启用抗锯齿
        g.SmoothingMode = SmoothingMode.AntiAlias;

        // 设置线条的颜色和宽度
        Pen pen = new Pen(Color.White, lineWidth);

        // 绘制横线
        g.DrawLine(pen, 0, picture.Height  / 2 + lineWidth / 2, picture.Width, picture.Height  / 2 + lineWidth / 2);
    }

    // 将绘制好的 Bitmap 显示在 PictureBox 中
    picture.Image = bmp;
}