winform中的控件做成圆角样式

各位牛人，我需要将winform中多个richtextbox、textbox、datagridview做成四个圆角样式，将groupbox做成只有右上角圆角，上面和右面有线条的样式，请问该怎么做呢？C#

正好近期在做类似的项目，可供参考哈

1. 创建一个继承自TextBox、DataGridView、GroupBox等控件类的子类，并重写其Paint事件。在该事件中，使用GraphicsPath对象绘制具有圆角边框的路径。

2. 使用同样继承自Control的子类，重写其OnResize、OnCreateControl这两个方法，调整圆角绘制路径的大小和位置。

以下是一个继承自TextBox的圆角控件的样例代码：

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

public class RoundTextBox : TextBox
{
    public RoundTextBox()
    {
        SetStyle(ControlStyles.UserPaint | ControlStyles.ResizeRedraw | ControlStyles.SupportsTransparentBackColor, true);
        BackColor = Color.Transparent;
        Font = new Font("Arial", 10);
    }

    protected override void OnResize(EventArgs e)
    {
        base.OnResize(e);
        Invalidate();
    }

    protected override void OnCreateControl()
    {
        base.OnCreateControl();
        Height = 25;
    }

    protected override void OnPaint(PaintEventArgs e)
    {
        e.Graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;

        Rectangle rectBorder = new Rectangle(0, 0, Width - 1, Height - 1);

        // 边框的宽度
        int borderWidth = 2;

        // 圆角半径
        int cornerRadius = 6;

        GraphicsPath borderPath = DrawRoundRect(rectBorder, cornerRadius, borderWidth, true, true, false, false);

        Brush backColorBrush = new SolidBrush(BackColor);
        e.Graphics.FillPath(backColorBrush, borderPath);

        var borderPen = new Pen(Color.FromArgb(255, 170, 170, 170), borderWidth);
        e.Graphics.DrawPath(borderPen, borderPath);

        // 在文本框中绘制文本
        base.OnPaint(e);
    }

    private static GraphicsPath DrawRoundRect(Rectangle rect, int radius, int borderWidth, bool leftTopCorner, bool rightTopCorner, bool rightBottomCorner, bool leftBottomCorner)
    {
        GraphicsPath path = new GraphicsPath();

        int x = rect.X;
        int y = rect.Y;
        int width = rect.Width;
        int height = rect.Height;

        int d = radius + radius;

        if (leftTopCorner)
        {
            path.AddArc(x, y, d, d, 180, 90);
            path.AddLine(x + radius, y, x + width - radius, y);
        }
        else
        {
            path.AddLine(x, y, x + width - radius, y);
        }

        if (rightTopCorner)
        {
            path.AddArc(x + width - d, y, d, d, 270, 90);
            path.AddLine(x + width, y + radius, x + width, y + height - radius);
        }
        else
        {
            path.AddLine(x + width, y, x + width, y + height - radius);
        }

        if (rightBottomCorner)
        {
            path.AddArc(x + width - d, y + height - d, d, d, 0, 90);
            path.AddLine(x + width - radius, y + height, x + radius, y + height);
        }
        else
        {
            path.AddLine(x + width, y + height, x + radius, y + height);
        }

        if (leftBottomCorner)
        {
            path.AddArc(x, y + height - d, d, d, 90, 90);
            path.AddLine(x, y + height - radius, x, y + radius);
        }
        else
        {
            path.AddLine(x, y + height, x, y + radius);
        }

        path.CloseFigure();

        return path;
    }
}

要绘制只有右上角圆角的GroupBox，可以根据需要继承GroupBox并使用相似的方式进行绘制。