将单选按钮中包含的小圆圈点的颜色更改为红色？

问题描述

| 在Winform Application中，如何使用VB.NET或C＃将单选按钮中包含的小圆圈（点）的颜色更改为红色？ 谢谢，谢谢 德威 ================================================== ======== 我将分享，可能对其他人有用。该程序有效。

Imports System.Drawing.drawing2d

Public Class Form1

Public Class MyRadioButton
    Inherits RadioButton

    Private m_OnColor As Color
    Private m_OffColor As Color

    Public Sub New(ByVal On_Color As Color,ByVal Off_Color As Color)
        m_OnColor = On_Color
        m_OffColor = Off_Color
        SetStyle(ControlStyles.SupportsTransparentBackColor,True)
        BackColor = Color.Transparent
    End Sub

    Public Property OnColor() As Color
        Get
            Return m_OnColor
        End Get
        Set(ByVal value As Color)
            m_OnColor = value
        End Set
    End Property

    Public Property OffColor() As Color
        Get
            Return m_OffColor
        End Get
        Set(ByVal value As Color)
            m_OffColor = value
        End Set
    End Property

    Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs)
        MyBase.OnPaint(e)

        Dim g As Graphics = e.Graphics
        g.SmoothingMode = SmoothingMode.AntiAlias

        Dim dotDiameter As Integer = ClientRectangle.Height - 17
        Dim innerRect As New RectangleF(1.8F,7.8F,dotDiameter,dotDiameter)

        If Me.Checked Then
            g.FillEllipse(New SolidBrush(OnColor),innerRect)
        Else
            g.FillEllipse(New SolidBrush(OffColor),innerRect)
        End If

        g.DrawString(Text,Font,New SolidBrush(ForeColor),dotDiameter + 17,1)
    End Sub

End Class


Dim objRadio As New MyRadioButton(Color.Blue,Color.Red)

Private Sub Form1_Load(ByVal sender As System.Object,ByVal e As System.EventArgs) Handles MyBase.Load
    objRadio.Location = New Point(100,100)
    objRadio.Visible = True
    Me.Controls.Add(objRadio)
End Sub

Private Sub Button1_Click(ByVal sender As System.Object,ByVal e As System.EventArgs) Handles Button1.Click
    If objRadio.Checked Then
        objRadio.Checked = False
    Else
        objRadio.Checked = True
    End If
End Sub


End Class

    

解决方法

        这是一个winforms示例，其中包含一个所有者绘制的列表框，该列表框模拟了可用于所需功能的单选按钮列表。 编辑：这是一个更深入的Winforms自定义控件示例。     ,        我以OP的VB代码为基础，并在MSDN帮助下使用PathGradientBrush提出了此派生的C＃类。如下图所示，绿色和红色按钮正在使用我的代码，两个蓝色按钮是常规版本。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Drawing;
using System.Drawing.Drawing2D;

namespace WindowsFormsApplication1
{
    public class ColouredRadioButton : RadioButton
    {
        // Fields
        private Color m_OnColour;
        private Color m_OffColour;
        private Rectangle m_glint;
        private Rectangle m_circle;
        private PathGradientBrush m_flareBrush;
        private Pen m_outline;

        // Properties
        public Color OnColour
        {
            get
            {
                return m_OnColour;
            }
            set
            {
                if ((value == Color.White) || (value == Color.Transparent))
                    m_OnColour = Color.Empty;
                else
                    m_OnColour = value;
            }
        }
        public Color OffColour
        {
            get
            {
                return m_OffColour;
            }
            set
            {
                if ((value == Color.White) || (value == Color.Transparent))
                    m_OffColour = Color.Empty;
                else
                    m_OffColour = value;
            }
        }

        // Constructor
        public ColouredRadioButton()
        {
            // Init
            m_circle = new Rectangle(2,5,7,7 /*Magic Numbers*/);
            m_glint = new Rectangle(3,6,4,4  /*Magic Numbers*/);
            m_outline = new Pen(new SolidBrush(Color.Black),1F /*Magic Numbers*/);

            // Generate Glint
            GraphicsPath Path = new GraphicsPath();
            Path.AddEllipse(m_glint);
            m_flareBrush = new PathGradientBrush(Path);
            m_flareBrush.CenterColor = Color.White;
            m_flareBrush.SurroundColors = new Color[] { Color.Transparent };
            m_flareBrush.FocusScales = new PointF(0.5F,0.5F/*Magic Numbers*/);

            // Allows for Overlaying
            SetStyle(ControlStyles.SupportsTransparentBackColor,true);
            BackColor = Color.Transparent;
        }

        // Methods
        protected override void OnPaint(PaintEventArgs e)
        {
            // Init
            base.OnPaint(e);
            Graphics g = e.Graphics;
            g.SmoothingMode = SmoothingMode.AntiAlias;

            // Overlay Graphic
            if (this.Checked)
            {
                if (OnColour != Color.Empty)
                {
                    g.FillEllipse(new SolidBrush(OnColour),m_circle);
                    g.FillEllipse(m_flareBrush,m_glint);
                    g.DrawEllipse(m_outline,m_circle);
                }
            }
            else
            {
                if (OffColour != Color.Empty)
                {
                    g.FillEllipse(new SolidBrush(OffColour),m_circle);
                }
            }
        }
    }
}

如果您好奇并想要我用来测试笔刷功能的红色大球代码，那么您就可以...

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Drawing.Drawing2D;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Paint(object sender,PaintEventArgs e)
        {
            e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;

            int Offset = 25;
            int BoxSize = 100;
            int GlintSize = (int)((double)BoxSize * ((double)3 / (double)4));
            Rectangle Circle = new Rectangle(Offset,Offset,BoxSize,BoxSize);
            Rectangle Glint = new Rectangle(Offset,GlintSize,GlintSize);

            //Debug
            //e.Graphics.FillRectangle(new SolidBrush(Color.Red),Circle);
            //e.Graphics.FillRectangle(new SolidBrush(Color.BlueViolet),Glint);

            //Generate Glint
            GraphicsPath P = new GraphicsPath();
            P.AddEllipse(Glint);
            PathGradientBrush FlareBrush = new PathGradientBrush(P);
            FlareBrush.CenterColor = Color.FromArgb(255,255,255);
            Color[] colors = { Color.Transparent };
            FlareBrush.SurroundColors = colors;

            e.Graphics.FillEllipse(new SolidBrush(Color.FromArgb(255,0)),Circle);
            e.Graphics.FillEllipse(FlareBrush,Glint);
            e.Graphics.DrawEllipse(new Pen(new SolidBrush(Color.Black),1F),Circle);
        }
    }
}