使用C#绘制矩形,我需要首先绘制每个边缘的弧我绘制矩形,然后我需要单击按钮它将在边缘绘制弧,我该怎么办？

我正在使用此代码来创建带有圆边的表单(FormBorderStyle = none):

[DllImport("Gdi32.dll", EntryPoint = "CreateRoundRectRgn")]
private static extern IntPtr CreateRoundRectRgn
(
    int nLeftRect, // x-coordinate of upper-left corner
    int nTopRect, // y-coordinate of upper-left corner
    int nRightRect, // x-coordinate of lower-right corner
    int nBottomRect, // y-coordinate of lower-right corner
    int nWidthEllipse, // height of ellipse
    int nHeightEllipse // width of ellipse
 );

public Form1()
{
    InitializeComponent();
    Region = System.Drawing.Region.FromHrgn(CreateRoundRectRgn(0, 0, Width, Height, 20, 20));
}

这是在Paint事件上设置自定义边框:

    ControlPaint.DrawBorder(e.Graphics, this.ClientRectangle, Color.Black, 5, ButtonBorderStyle.Solid, Color.Black, 5, ButtonBorderStyle.Solid, Color.Black, 5, ButtonBorderStyle.Solid, Color.Black, …

我有一个Form其中包含：

1. a TrackBar（最小值 = 1，最大值 = 200，表示缩放百分比）；
2. 与.UserControl​BorderStyle = BorderStyle.None

相关代码

表格1

来自设计师代码

trackBar1.Value = 100;
BackColor = Color.Gray;

从代码隐藏

private void trackBar1_Scroll(object sender, EventArgs e)
{
    userControl11.SetZoomFactor(trackBar1.Value / 100F);
}

用户控制1

internal float MyBaseWidth;

public UserControl1()
{
    InitializeComponent();

    MyBaseWidth = Width;

    SetZoomFactor(1);
}

protected override void OnPaint(PaintEventArgs e)
{
    base.OnPaint(e);

    e.Graphics.SmoothingMode = SmoothingMode.HighQuality;
    e.Graphics.CompositingQuality = CompositingQuality.HighQuality;
    e.Graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;

    Pen p = new Pen(Color.Yellow);
    e.Graphics.DrawPath(p, GraphicsPathWithBorder);
}

internal GraphicsPath GraphicsPathWithBorder;

internal void SetZoomFactor(float …