C#

using System;
using System.Drawing;
using System.Drawing.Design;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
 
public class Form1 : System.Windows.Forms.Form
{
  private System.Windows.Forms.PropertyGrid propertyGrid1;
  private System.Windows.Forms.RadioButton radioButton1;
  private CustomRadioButton radioButton2;
  private System.Windows.Forms.GroupBox groupBox1;
 
  public Form1()
  {
    InitializeComponent();
  }
 
  private void InitializeComponent()
  {
    this.propertyGrid1 = new System.Windows.Forms.PropertyGrid();
    this.radioButton1 = new System.Windows.Forms.RadioButton();
    this.radioButton2 = new CustomRadioButton();
    this.groupBox1 = new System.Windows.Forms.GroupBox();
    this.groupBox1.SuspendLayout();
    this.SuspendLayout();
    // 
    // propertyGrid1
    // 
    this.propertyGrid1.CommandsVisibleIfAvailable = true;
    this.propertyGrid1.LargeButtons = false;
    this.propertyGrid1.LineColor = System.Drawing.SystemColors.ScrollBar;
    this.propertyGrid1.Location = new System.Drawing.Point(8, 88);
    this.propertyGrid1.Name = "propertyGrid1";
    this.propertyGrid1.SelectedObject = this.radioButton1;
    this.propertyGrid1.Size = new System.Drawing.Size(280, 264);
    this.propertyGrid1.TabIndex = 0;
    this.propertyGrid1.Text = "propertyGrid1";
    this.propertyGrid1.ViewBackColor = System.Drawing.SystemColors.Window;
    this.propertyGrid1.ViewForeColor = System.Drawing.SystemColors.WindowText;
    // 
    // radioButton1
    // 
    this.radioButton1.Checked = true;
    this.radioButton1.Location = new System.Drawing.Point(8, 16);
    this.radioButton1.Name = "radioButton1";
    this.radioButton1.Size = new System.Drawing.Size(160, 24);
    this.radioButton1.TabIndex = 1;
    this.radioButton1.TabStop = true;
    this.radioButton1.Text = "BackgroundImage ...";
    this.radioButton1.CheckedChanged += new System.EventHandler(this.switchObject);
    // 
    // radioButton2
    // 
    this.radioButton2.Location = new System.Drawing.Point(8, 40);
    this.radioButton2.Name = "radioButton2";
    this.radioButton2.Size = new System.Drawing.Size(160, 24);
    this.radioButton2.TabIndex = 2;
    this.radioButton2.Text = "No BackgroundImage ...";
    this.radioButton2.CheckedChanged += new System.EventHandler(this.switchObject);
    // 
    // groupBox1
    // 
    this.groupBox1.Controls.Add(this.radioButton1);
    this.groupBox1.Controls.Add(this.radioButton2);
    this.groupBox1.Location = new System.Drawing.Point(8, 8);
    this.groupBox1.Name = "groupBox1";
    this.groupBox1.Size = new System.Drawing.Size(280, 72);
    this.groupBox1.TabIndex = 3;
    this.groupBox1.TabStop = false;
    // 
    // Form1
    // 
    this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
    this.ClientSize = new System.Drawing.Size(296, 365);
    this.Controls.Add(this.groupBox1);
    this.Controls.Add(this.propertyGrid1);
    this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog;
    this.MaximizeBox = false;
    this.Name = "Form1";
    this.Text = "Example";
    this.groupBox1.ResumeLayout(false);
    this.ResumeLayout(false);
 
  }
 
  [STAThread]
  static void Main() 
  {
    Application.Run(new Form1());
  }
 
  private void switchObject(object sender, System.EventArgs e)
  {
    RadioButton radio = sender as RadioButton;
    if (radio != null && radio.Checked) this.propertyGrid1.SelectedObject = radio;
  }
}
 
class CustomRadioButton : RadioButton
{
  [Editor(typeof(CustomRadioButtonImageEditor), typeof(UITypeEditor))]
  public override Image BackgroundImage
  {
    get
    {
      return base.BackgroundImage;
    }
    set
    {
      base.BackgroundImage = value;
    }
  }
 
  class CustomRadioButtonImageEditor : UITypeEditor
  {
    public override UITypeEditorEditStyle GetEditStyle(ITypeDescriptorContext context)
    {
      return UITypeEditorEditStyle.None;
    }
  }
}

[Editor(typeof(CParkInfo))]
public class CPartInfo : UITypeEditor
{
  // ...
}

Do you want to know more?

<br />
private Regex emailReg = new Regex(<br />
   @"(?<Username>\w[-.\w]*)@(?<Host>[-a-z0-9]+(\.[-a-z0-9]+)*\." +<br />
   @"(com|edu|gov|int|mil|net|org|biz|info|name|museum|coop|aero|[a-z][a-z]))",<br />
   RegexOptions.IgnoreCase);<br />