C# 如何更改组框上边框的颜色？

在C#.NET中，我试图通过编程更改组框中边框的颜色

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更新：在切换到.NET之前，我在winforms系统上工作时问过这个问题。

我不确定这是否适用于所有情况，但多亏了这个线程，我们很快通过以下方式以编程方式连接到Paint事件：

GroupBox box = new GroupBox();
[...]
box.Paint += delegate(object o, PaintEventArgs p)
{
    p.Graphics.Clear(someColorHere);
};

---

干杯

基于上一个答案，一个更好的解决方案包括组框标签：

groupBox1.Paint += PaintBorderlessGroupBox;

private void PaintBorderlessGroupBox(object sender, PaintEventArgs p)
{
  GroupBox box = (GroupBox)sender;
  p.Graphics.Clear(SystemColors.Control);
  p.Graphics.DrawString(box.Text, box.Font, Brushes.Black, 0, 0);
}

---

您可能希望调整文本的x/y，但对于我的使用，这正好。

只需将任何对象（不仅仅是按钮）上的绘制操作设置为该方法即可绘制边框

    private void UserControl1_Paint(object sender, PaintEventArgs e)
    {
        ControlPaint.DrawBorder(e.Graphics, this.ClientRectangle, Color.Red, ButtonBorderStyle.Solid);

    }

它仍然不会像原版一样漂亮和圆润，但它要简单得多。

只需添加绘画事件即可

    private void groupBox1_Paint(object sender, PaintEventArgs e)
    {
        GroupBox box = sender as GroupBox;
        DrawGroupBox(box, e.Graphics, Color.Red, Color.Blue);
    }


    private void DrawGroupBox(GroupBox box, Graphics g, Color textColor, Color borderColor)
    {
        if (box != null)
        {
            Brush textBrush = new SolidBrush(textColor);
            Brush borderBrush = new SolidBrush(borderColor);
            Pen borderPen = new Pen(borderBrush);
            SizeF strSize = g.MeasureString(box.Text, box.Font);
            Rectangle rect = new Rectangle(box.ClientRectangle.X,
                                           box.ClientRectangle.Y + (int)(strSize.Height / 2),
                                           box.ClientRectangle.Width - 1,
                                           box.ClientRectangle.Height - (int)(strSize.Height / 2) - 1);

            // Clear text and border
            g.Clear(this.BackColor);

            // Draw text
            g.DrawString(box.Text, box.Font, textBrush, box.Padding.Left, 0);

            // Drawing Border
            //Left
            g.DrawLine(borderPen, rect.Location, new Point(rect.X, rect.Y + rect.Height));
            //Right
            g.DrawLine(borderPen, new Point(rect.X + rect.Width, rect.Y), new Point(rect.X + rect.Width, rect.Y + rect.Height));
            //Bottom
            g.DrawLine(borderPen, new Point(rect.X, rect.Y + rect.Height), new Point(rect.X + rect.Width, rect.Y + rect.Height));
            //Top1
            g.DrawLine(borderPen, new Point(rect.X, rect.Y), new Point(rect.X + box.Padding.Left, rect.Y));
            //Top2
            g.DrawLine(borderPen, new Point(rect.X + box.Padding.Left + (int)(strSize.Width), rect.Y), new Point(rect.X + rect.Width, rect.Y));
        }
    }

---

我与一些新手可能更容易理解的东西达成了相同的边界：

    private void groupSchitaCentru_Paint(object sender, PaintEventArgs e)
    {
        Pen blackPen = new Pen(Color.Black, 2);
        Point pointTopLeft = new Point(0, 7);
        Point pointBottomLeft = new Point(0, groupSchitaCentru.ClientRectangle.Height);
        Point pointTopRight = new Point(groupSchitaCentru.ClientRectangle.Width, 7);
        Point pointBottomRight = new Point(groupSchitaCentru.ClientRectangle.Width, groupSchitaCentru.ClientRectangle.Height);

        e.Graphics.DrawLine(blackPen, pointTopLeft, pointBottomLeft);
        e.Graphics.DrawLine(blackPen, pointTopLeft, pointTopRight);
        e.Graphics.DrawLine(blackPen, pointBottomRight, pointTopRight);
        e.Graphics.DrawLine(blackPen, pointBottomLeft, pointBottomRight);
    }

在GroupBox控件上设置绘制事件。在本例中，我的控件名为“groupSchitaCentru”。由于其参数e，需要此事件

使用System.Drawing.pen类设置笔对象：

设置表示控件所表示矩形角点的点。使用控件的属性ClientRectangle获取其维度。 我使用TopLeft（0,7）是因为我想尊重控件的边界，并围绕控件及其文本绘制线。 要获取有关坐标系的更多信息，请在此处漫游：

---

我不知道，这可能有助于某些人实现边界调整。FWIW，这是我使用的实现。它是GroupBox的子项，但不仅允许设置边框颜色，还允许设置边框的厚度和圆角的半径。此外，您还可以为GroupBox标签设置所需的缩进量，并从右侧使用负缩进

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

namespace BorderedGroupBox
{
    public class BorderedGroupBox : GroupBox
    {
        private Color _borderColor = Color.Black;
        private int _borderWidth = 2;
        private int _borderRadius = 5;
        private int _textIndent = 10;

        public BorderedGroupBox() : base()
        {
            InitializeComponent();
            this.Paint += this.BorderedGroupBox_Paint;
        }

        public BorderedGroupBox(int width, float radius, Color color) : base()
        {
            this._borderWidth = Math.Max(1,width);
            this._borderColor = color;
            this._borderRadius = Math.Max(0,radius);
            InitializeComponent();
            this.Paint += this.BorderedGroupBox_Paint;
        }

        public Color BorderColor
        {
            get => this._borderColor;
            set
            {
                this._borderColor = value;
                DrawGroupBox();
            }
        }

        public int BorderWidth
        {
            get => this._borderWidth;
            set
            {
                if (value > 0)
                {
                    this._borderWidth = Math.Min(value, 10);
                    DrawGroupBox();
                }
            }
        }

        public int BorderRadius
        {
            get => this._borderRadius;
            set
            {   // Setting a radius of 0 produces square corners...
                if (value >= 0)
                {
                    this._borderRadius = value;
                    this.DrawGroupBox();
                }
            }
        }

        public int LabelIndent
        {
            get => this._textIndent;
            set
            {
                this._textIndent = value;
                this.DrawGroupBox();
            }
        }

        private void BorderedGroupBox_Paint(object sender, PaintEventArgs e) =>
            DrawGroupBox(e.Graphics);

        private void DrawGroupBox() =>
            this.DrawGroupBox(this.CreateGraphics());

        private void DrawGroupBox(Graphics g)
        {
            Brush textBrush = new SolidBrush(this.ForeColor);
            SizeF strSize = g.MeasureString(this.Text, this.Font);

            Brush borderBrush = new SolidBrush(this.BorderColor);
            Pen borderPen = new Pen(borderBrush,(float)this._borderWidth);
            Rectangle rect = new Rectangle(this.ClientRectangle.X,
                                            this.ClientRectangle.Y + (int)(strSize.Height / 2),
                                            this.ClientRectangle.Width - 1,
                                            this.ClientRectangle.Height - (int)(strSize.Height / 2) - 1);

            Brush labelBrush = new SolidBrush(this.BackColor);

            // Clear text and border
            g.Clear(this.BackColor);

            // Drawing Border (added "Fix" from Jim Fell, Oct 6, '18)
            int rectX = (0 == this._borderWidth % 2) ? rect.X + this._borderWidth / 2 : rect.X + 1 + this._borderWidth / 2;
            int rectHeight = (0 == this._borderWidth % 2) ? rect.Height - this._borderWidth / 2 : rect.Height - 1 - this._borderWidth / 2;
            // NOTE DIFFERENCE: rectX vs rect.X and rectHeight vs rect.Height
            g.DrawRoundedRectangle(borderPen, rectX, rect.Y, rect.Width, rectHeight, (float)this._borderRadius);

            // Draw text
            if (this.Text.Length > 0)
            {
                // Do some work to ensure we don't put the label outside
                // of the box, regardless of what value is assigned to the Indent:
                int width = (int)rect.Width, posX;
                posX = (this._textIndent < 0) ? Math.Max(0-width,this._textIndent) : Math.Min(width, this._textIndent);
                posX = (posX < 0) ? rect.Width + posX - (int)strSize.Width : posX;
                g.FillRectangle(labelBrush, posX, 0, strSize.Width, strSize.Height);
                g.DrawString(this.Text, this.Font, textBrush, posX, 0);
            }
        }

        #region Component Designer generated code
        /// <summary>Required designer variable.</summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>Clean up any resources being used.</summary>
        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
                components.Dispose();

            base.Dispose(disposing);
        }

        /// <summary>Required method for Designer support - Don't modify!</summary>
        private void InitializeComponent() => components = new System.ComponentModel.Container();
        #endregion
    }
}

使用系统；
使用系统图；
使用System.Windows.Forms；
命名空间边框组框
{
公共类BorderedGroupBox:GroupBox
{
私有颜色_borderColor=颜色.黑色；
私有int_borderWidth=2；
私有int_borderRadius=5；
私有int _textdindent=10；
public BorderedGroupBox（）：base（）
{
初始化组件（）；
this.Paint+=this.BorderedGroupBox\u Paint；
}
公共BorderedGroupBox（int-width、float-radius、Color-Color）：base（）
{
此参数为.u borderWidth=Math.Max（1，宽度）；
这个。_borderColor=颜色；
这个._borderRadius=Math.Max（0，半径）；
初始化组件（）；
this.Paint+=this.BorderedGroupBox\u Paint；
}
公共颜色边框颜色
{
get=>这个；
设置
{
这是。_borderColor=值；
DrawGroupBox（）；
}
}
公共整数边框宽度
{
get=>这个；
设置
{
如果（值>0）
{
此值为.u borderWidth=Math.Min（值为10）；
DrawGroupBox（）；
}
}
}
公共整数边界半径
{
get=>这个；
设置
{//将半径设置为0将生成方形角。。。
如果（值>=0）
{
这是。_borderRadius=值；
这个.DrawGroupBox（）；
}
}
}
公共国际标签
{
get=>这个；
设置
{
此值为.\u textIndent=值；
这个.DrawGroupBox（）；
}
}
私有void BorderedGroupBox_Paint（对象发送方，PaintEventArgs e）=>
DrawGroupBox（如图形）；
私有void DrawGroupBox（）=>
this.DrawGroupBox（this.CreateGraphics（））；
专用void DrawGroupBox（图形g）
{
笔刷文本笔刷=新的SolidBrush（this.ForeColor）；
SizeF strSize=g.MeasureString（this.Text，this.Font）；
画笔边框画笔=新的SolidBrush（this.BorderColor）；
画笔边框画笔=新画笔（边框画笔，（浮动）此。_borderWidth）；
矩形rect=新矩形（此.ClientRectangle.X，
此.ClientRectangle.Y+（int）（strSize.Height/2），
此.ClientRectangle.Width-1，
this.ClientRectangle.Height-（int）（strize.Height/2）-1）；
Brush labelBrush=新的SolidBrush（此背景色）；
//明文和边框
g、 清晰（此为背景色）；
//绘图边框（添加了Jim Fall的“修复”，10月6日，18日）
int rectX=（0==此。_borderWidth%2）？rect.X+此。_borderWidth/2:rect.X+1+此。_borderWidth/2；
int rectHeight=（0==此._borderWidth%2）？rect.Height-此._borderWidth/2:rect.Height-1-此._borderWidth/2；
//注意区别：rectX与rect.X和rectHeight与rect.Height
g、 DrawRoundedRectangle（边界笔、矩形X、矩形Y、矩形宽度、矩形高度、（浮动）此边界半径）；
//绘制文本
如果（this.Text.Length>0）
{
//做一些工作确保我们不会把标签放在外面
//无论为缩进指定了什么值，框的：
int-width=（int）rect.width，posX；
posX=（this.\u textdindent<0）？Math.Max（0-width，this.\u textdindent）：Math.Min（width，this.\u textdindent）；
posX=（posX<0）？rect.Width+posX-（int）strSize.Width:posX；
g、 圆角矩形（labelBrush，posX，0，strSize.Width，strSize.Height）；
g、 抽绳（this.Text，this.Font，textBrush，posX，0）；
}
static class GraphicsExtension
{
    private static GraphicsPath GenerateRoundedRectangle(
        this Graphics graphics,
        RectangleF rectangle,
        float radius)
    {
        float diameter;
        GraphicsPath path = new GraphicsPath();
        if (radius <= 0.0F)
        {
            path.AddRectangle(rectangle);
            path.CloseFigure();
            return path;
        }
        else
        {
            if (radius >= (Math.Min(rectangle.Width, rectangle.Height)) / 2.0)
                return graphics.GenerateCapsule(rectangle);
            diameter = radius * 2.0F;
            SizeF sizeF = new SizeF(diameter, diameter);
            RectangleF arc = new RectangleF(rectangle.Location, sizeF);
            path.AddArc(arc, 180, 90);
            arc.X = rectangle.Right - diameter;
            path.AddArc(arc, 270, 90);
            arc.Y = rectangle.Bottom - diameter;
            path.AddArc(arc, 0, 90);
            arc.X = rectangle.Left;
            path.AddArc(arc, 90, 90);
            path.CloseFigure();
        }
        return path;
    }

    private static GraphicsPath GenerateCapsule(
        this Graphics graphics,
        RectangleF baseRect)
    {
        float diameter;
        RectangleF arc;
        GraphicsPath path = new GraphicsPath();
        try
        {
            if (baseRect.Width > baseRect.Height)
            {
                diameter = baseRect.Height;
                SizeF sizeF = new SizeF(diameter, diameter);
                arc = new RectangleF(baseRect.Location, sizeF);
                path.AddArc(arc, 90, 180);
                arc.X = baseRect.Right - diameter;
                path.AddArc(arc, 270, 180);
            }
            else if (baseRect.Width < baseRect.Height)
            {
                diameter = baseRect.Width;
                SizeF sizeF = new SizeF(diameter, diameter);
                arc = new RectangleF(baseRect.Location, sizeF);
                path.AddArc(arc, 180, 180);
                arc.Y = baseRect.Bottom - diameter;
                path.AddArc(arc, 0, 180);
            }
            else path.AddEllipse(baseRect);
        }
        catch { path.AddEllipse(baseRect); }
        finally { path.CloseFigure(); }
        return path;
    }

    /// <summary>
    /// Draws a rounded rectangle specified by a pair of coordinates, a width, a height and the radius
    /// for the arcs that make the rounded edges.
    /// </summary>
    /// <param name="brush">System.Drawing.Pen that determines the color, width and style of the rectangle.</param>
    /// <param name="x">The x-coordinate of the upper-left corner of the rectangle to draw.</param>
    /// <param name="y">The y-coordinate of the upper-left corner of the rectangle to draw.</param>
    /// <param name="width">Width of the rectangle to draw.</param>
    /// <param name="height">Height of the rectangle to draw.</param>
    /// <param name="radius">The radius of the arc used for the rounded edges.</param>
    public static void DrawRoundedRectangle(
        this Graphics graphics,
        Pen pen,
        float x,
        float y,
        float width,
        float height,
        float radius)
    {
        RectangleF rectangle = new RectangleF(x, y, width, height);
        GraphicsPath path = graphics.GenerateRoundedRectangle(rectangle, radius);
        SmoothingMode old = graphics.SmoothingMode;
        graphics.SmoothingMode = SmoothingMode.AntiAlias;
        graphics.DrawPath(pen, path);
        graphics.SmoothingMode = old;
    }

    /// <summary>
    /// Draws a rounded rectangle specified by a pair of coordinates, a width, a height and the radius
    /// for the arcs that make the rounded edges.
    /// </summary>
    /// <param name="brush">System.Drawing.Pen that determines the color, width and style of the rectangle.</param>
    /// <param name="x">The x-coordinate of the upper-left corner of the rectangle to draw.</param>
    /// <param name="y">The y-coordinate of the upper-left corner of the rectangle to draw.</param>
    /// <param name="width">Width of the rectangle to draw.</param>
    /// <param name="height">Height of the rectangle to draw.</param>
    /// <param name="radius">The radius of the arc used for the rounded edges.</param>

    public static void DrawRoundedRectangle(
        this Graphics graphics,
        Pen pen,
        int x,
        int y,
        int width,
        int height,
        int radius)
    {
        graphics.DrawRoundedRectangle(
            pen,
            Convert.ToSingle(x),
            Convert.ToSingle(y),
            Convert.ToSingle(width),
            Convert.ToSingle(height),
            Convert.ToSingle(radius));
    }
}