Creating an event for a component.

   
 


using System;
using System.Collections;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Windows.Forms;


public class CompoundControl : System.Windows.Forms.UserControl {
    public delegate Boolean ValueChangedEventHandler(int nValue);
    private System.Windows.Forms.Label label1;
    private System.Windows.Forms.ComboBox comboBox1;
    public event ValueChangedEventHandler Changed;

    public CompoundControl() {
        this.comboBox1 = new System.Windows.Forms.ComboBox();
        this.label1 = new System.Windows.Forms.Label();
        this.SuspendLayout();
        this.comboBox1.DropDownWidth = 121;
        this.comboBox1.Items.AddRange(new object[] {"A","B","C","F","G","N"});
        this.comboBox1.Location = new System.Drawing.Point(24, 48);
        this.comboBox1.Size = new System.Drawing.Size(200, 21);
        this.comboBox1.Text = "comboBox1";
        this.comboBox1.SelectedIndexChanged += new System.EventHandler(this.OnSelectionIndexChange);
        this.label1.Location = new System.Drawing.Point(16, 24);
        this.label1.Text = "Select An Entry";
        this.Controls.AddRange(new System.Windows.Forms.Control[] {
        this.comboBox1,
        this.label1});
        this.Size = new System.Drawing.Size(240, 96);
        this.ResumeLayout(false);
    }
    private void OnSelectionIndexChange(object sender,
        System.EventArgs e) {
        if (Changed != null)
            Changed(this.comboBox1.SelectedIndex);
    }
}


public class Form1 : System.Windows.Forms.Form {
    private System.ComponentModel.Container components = null;
    private CompoundControl compoundcomponent1 = null;

    public Form1() {
        this.compoundcomponent1 = new CompoundControl();
        this.compoundcomponent1.Location = new System.Drawing.Point(24, 50);
        this.compoundcomponent1.Name = "compound1";
        this.compoundcomponent1.Size = new System.Drawing.Size(250, 100);
        this.compoundcomponent1.Changed += new CompoundControl.ValueChangedEventHandler(OnChanged);
        this.components = new System.ComponentModel.Container();
        this.Size = new System.Drawing.Size(300, 300);
        this.Controls.AddRange(new System.Windows.Forms.Control[]{this.compoundcomponent1,});
    }
    private bool OnChanged(int nIndex) {
        MessageBox.Show(this, "New Index!" + nIndex);
        return true;
    }

    [STAThread]
    static void Main() {
        Application.Run(new Form1());
    }
}

    


Define user control


   

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

public class Form1 : Form
{

    private ClockUserControl clockUserControl1;

  public Form1() {
        InitializeComponent();
  }


      private void InitializeComponent()
      {
         this.clockUserControl1 = new ClockUserControl();
         this.SuspendLayout();
         // 
         // clockUserControl1
         // 
         this.clockUserControl1.Location = new System.Drawing.Point(12, 12);
         this.clockUserControl1.Name = "clockUserControl1";
         this.clockUserControl1.Size = new System.Drawing.Size(154, 74);
         this.clockUserControl1.TabIndex = 0;
         // 
         // Clock
         // 
         this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
         this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
         this.ClientSize = new System.Drawing.Size(178, 99);
         this.Controls.Add(this.clockUserControl1);
         this.Name = "Clock";
         this.Text = "Clock";
         this.ResumeLayout(false);

      }
  [STAThread]
  static void Main()
  {
    Application.EnableVisualStyles();
    Application.Run(new Form1());
  }

}


public class ClockUserControl : UserControl
{
      private System.Windows.Forms.Label displayLabel;
      private System.Windows.Forms.Timer clockTimer;
      
      public ClockUserControl() {
         InitializeComponent();
      }  

      private void clockTimer_Tick(object sender, EventArgs e) {
         displayLabel.Text = DateTime.Now.ToLongTimeString();
      }
      private void InitializeComponent()
      {
         this.displayLabel = new System.Windows.Forms.Label();
         this.clockTimer = new System.Windows.Forms.Timer( new System.ComponentModel.Container() );
         this.SuspendLayout();
         // 
         // displayLabel
         // 
         this.displayLabel.BackColor = System.Drawing.SystemColors.ActiveCaptionText;
         this.displayLabel.Font = new System.Drawing.Font( "Microsoft Sans Serif", 12F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ( ( byte ) ( 0 ) ) );
         this.displayLabel.Location = new System.Drawing.Point( 4, 10 );
         this.displayLabel.Name = "displayLabel";
         this.displayLabel.Size = new System.Drawing.Size( 143, 52 );
         this.displayLabel.TabIndex = 0;
         this.displayLabel.Text = "12:55:55 AM";
         this.displayLabel.TextAlign = System.Drawing.ContentAlignment.MiddleCenter;
         // 
         // clockTimer
         // 
         this.clockTimer.Enabled = true;
         this.clockTimer.Interval = 1000;
         this.clockTimer.Tick += new System.EventHandler( this.clockTimer_Tick );
         // 
         // ClockUserControl
         // 
         this.AutoScaleDimensions = new System.Drawing.SizeF( 6F, 13F );
         this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
         this.BackColor = System.Drawing.Color.White;
         this.Controls.Add( this.displayLabel );
         this.Name = "ClockUserControl";
         this.Size = new System.Drawing.Size( 150, 72 );
         this.ResumeLayout( false );

      }

}


           
          


Draw a Custom Control

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

public class SimpleCustomControl : System.Windows.Forms.Control {
    public SimpleCustomControl() {
        InitializeComponent();
    }
    private void SimpleCustomControl_Paint(object sender, PaintEventArgs e) {
        Graphics g = e.Graphics;
        g.FillRectangle(Brushes.Yellow, ClientRectangle);
        g.DrawString("Hello, world", Font, Brushes.Black, 0, 0);
    }
    private void InitializeComponent() {
        this.SuspendLayout();
        this.Paint += new System.Windows.Forms.PaintEventHandler(this.SimpleCustomControl_Paint);
        this.ResumeLayout(false);
    }
}


public class Form1 : Form {
    public Form1() {
        InitializeComponent();
    }
    private void InitializeComponent() {
        this.simpleCustomControl1 = new SimpleCustomControl();
        this.SuspendLayout();

        this.simpleCustomControl1.Location = new System.Drawing.Point(12, 12);
        this.simpleCustomControl1.Size = new System.Drawing.Size(178, 110);
        this.simpleCustomControl1.Text = "simpleCustomControl1";

        this.AutoScaleDimensions = new System.Drawing.SizeF(8F, 16F);
        this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
        this.ClientSize = new System.Drawing.Size(292, 268);
        this.Controls.Add(this.simpleCustomControl1);
        this.ResumeLayout(false);
    }
    private SimpleCustomControl simpleCustomControl1;
    [STAThread]
    static void Main() {
        Application.EnableVisualStyles();
        Application.Run(new Form1());
    }
}

    


subclass System.Windows.Forms.UserControl to create custom control

   
 


using System;
using System.Collections;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Windows.Forms;

public class UserControl1 : System.Windows.Forms.UserControl {
    private System.ComponentModel.Container components = null;

    public UserControl1() {
        this.Name = "UserControl1";
        this.Paint += new
         System.Windows.Forms.PaintEventHandler(this.OnPaint);

    }


    private void OnPaint(object sender,
         System.Windows.Forms.PaintEventArgs e) {
        e.Graphics.DrawString("Hello world", Font,
           new SolidBrush(Color.Blue), ClientRectangle);
    }
}
public class Form1 : System.Windows.Forms.Form {
    private System.ComponentModel.Container components = null;
    private System.Windows.Forms.Label label1;
    private UserControl1 control1;

    public Form1() {
        this.control1 = new UserControl1();
        this.label1 = new System.Windows.Forms.Label();
        this.SuspendLayout();
        this.control1.Location = new System.Drawing.Point(32, 48);
        this.control1.Size = new System.Drawing.Size(80, 24);
        this.label1.Location = new System.Drawing.Point(32, 24);
        this.label1.Size = new System.Drawing.Size(144, 24);
        this.label1.Text = "Custom Control:";
        this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
        this.ClientSize = new System.Drawing.Size(292, 273);
        this.Controls.AddRange(new System.Windows.Forms.Control[] {
        this.label1,
        this.control1});
        this.ResumeLayout(false);
    }

    [STAThread]
    static void Main() {
        Application.Run(new Form1());
    }
}

    


UpDown Derived

/*
Professional Windows GUI Programming Using C#
by Jay Glynn, Csaba Torok, Richard Conway, Wahid Choudhury,
Zach Greenvoss, Shripad Kulkarni, Neil Whitlow

Publisher: Peer Information
ISBN: 1861007663
*/

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace UpDown_Derived
{
///

/// Summary description for UpDownDerived.
///

public class UpDownDerived : System.Windows.Forms.Form
{
///

/// Required designer variable.
///

private System.ComponentModel.Container components = null;
private System.Windows.Forms.Label label1;
private MyUpDownControl mDC = null ;
public UpDownDerived()
{
//
// Required for Windows Form Designer support
//
InitializeComponent();

//
// TODO: Add any constructor code after InitializeComponent call
//
}

///

/// Clean up any resources being used.
///

protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}

#region Windows Form Designer generated code
///

/// Required method for Designer support – do not modify
/// the contents of this method with the code editor.
///

private void InitializeComponent()
{
this.mDC = new UpDown_Derived.MyUpDownControl();
this.label1 = new System.Windows.Forms.Label();
this.SuspendLayout();
//
// mDC
//
this.mDC.Items.Add(“FRANCE”);
this.mDC.Items.Add(“ITALY”);
this.mDC.Items.Add(“USA”);
this.mDC.Items.Add(“UK”);
this.mDC.Items.Add(“AUSTRALIA”);
this.mDC.Items.Add(“INDIA”);
this.mDC.Items.Add(“ZAMBIA”);
this.mDC.Items.Add(“MALASYIA”);
this.mDC.Location = new System.Drawing.Point(40, 40);
this.mDC.Name = “mDC”;
this.mDC.TabIndex = 0;
//
// label1
//
this.label1.Location = new System.Drawing.Point(16, 16);
this.label1.Name = “label1”;
this.label1.Size = new System.Drawing.Size(200, 16);
this.label1.TabIndex = 1;
this.label1.Text = “Derived DomainUpDown Controller”;
//
// UpDownDerived
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(248, 85);
this.Controls.AddRange(new System.Windows.Forms.Control[] {
this.label1,
this.mDC});
this.Name = “UpDownDerived”;
this.Text = “My Domain Controller”;
this.Load += new System.EventHandler(this.UpDownDerived_Load);
this.ResumeLayout(false);

}
#endregion

///

/// The main entry point for the application.
///

[STAThread]
static void Main()
{
Application.Run(new UpDownDerived());
}

private void UpDownDerived_Load(object sender, System.EventArgs e)
{
}
}
///

/// Summary description for MyUpDownControl.
///

public class MyUpDownControl : System.Windows.Forms.DomainUpDown
{
private int currentPos =0;
private string DisplayText =””;
public MyUpDownControl()
{
// Populate the control with items
Items.Add(“FRANCE”);
Items.Add(“ITALY”);
Items.Add(“USA”);
Items.Add(“UK”);
Items.Add(“AUSTRALIA”);
Items.Add(“INDIA”);
Items.Add(“ZAMBIA”);
Items.Add(“MALASYIA”);

}

public override void DownButton()
{
// Check if the Down Arrow is clicked
currentPos ++;
if ( currentPos >= Items.Count )
currentPos = 0 ;
UpdateEditText();
}

public override void UpButton()
{
// Check if the Up Arrow is clicked
currentPos — ;
if ( currentPos < 0 ) currentPos = Items.Count-1 ; UpdateEditText(); } protected override void UpdateEditText() { // Update the EditBox DisplayText = (string)this.Items[currentPos ]; this.Text = DisplayText; } public void Sort() { if ( this.Sorted ) this.Sorted= false ; else this.Sorted= true ; if ( this.Sorted ) this.Sort() ; UpdateEditText() ; } } } [/csharp]

UpDown Control


   

/*
Professional Windows GUI Programming Using C#
by Jay Glynn, Csaba Torok, Richard Conway, Wahid Choudhury, 
   Zach Greenvoss, Shripad Kulkarni, Neil Whitlow

Publisher: Peer Information
ISBN: 1861007663
*/
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace UpDown
{
    /// <summary>
    /// Summary description for UpDown.
    /// </summary>
    public class UpDown : System.Windows.Forms.Form
    {
      private System.Windows.Forms.Button button2;
      private System.Windows.Forms.TextBox textBox1;
      private System.Windows.Forms.Button button1;
      private System.Windows.Forms.DomainUpDown UPDOWN_DOMAIN;
      private System.Windows.Forms.Label label1;
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.Container components = null;

        public UpDown()
        {
            //
            // Required for Windows Form Designer support
            //
            InitializeComponent();

            //
            // TODO: Add any constructor code after InitializeComponent call
            //
        }

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        protected override void Dispose( bool disposing )
        {
            if( disposing )
            {
                if (components != null) 
                {
                    components.Dispose();
                }
            }
            base.Dispose( disposing );
        }

        #region Windows Form Designer generated code
        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
         this.button2 = new System.Windows.Forms.Button();
         this.textBox1 = new System.Windows.Forms.TextBox();
         this.button1 = new System.Windows.Forms.Button();
         this.UPDOWN_DOMAIN = new System.Windows.Forms.DomainUpDown();
         this.label1 = new System.Windows.Forms.Label();
         this.SuspendLayout();
         // 
         // button2
         // 
         this.button2.Location = new System.Drawing.Point(136, 80);
         this.button2.Name = "button2";
         this.button2.TabIndex = 8;
         this.button2.Text = "Add Item";
         // 
         // textBox1
         // 
         this.textBox1.Location = new System.Drawing.Point(24, 80);
         this.textBox1.Name = "textBox1";
         this.textBox1.TabIndex = 7;
         this.textBox1.Text = "";
         // 
         // button1
         // 
         this.button1.Location = new System.Drawing.Point(264, 40);
         this.button1.Name = "button1";
         this.button1.Size = new System.Drawing.Size(64, 23);
         this.button1.TabIndex = 6;
         this.button1.Text = "Remove";
         // 
         // UPDOWN_DOMAIN
         // 
         this.UPDOWN_DOMAIN.BackColor = System.Drawing.Color.FromArgb(((System.Byte)(255)), ((System.Byte)(192)), ((System.Byte)(192)));
         this.UPDOWN_DOMAIN.Font = new System.Drawing.Font("Microsoft Sans Serif", 12F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((System.Byte)(0)));
         this.UPDOWN_DOMAIN.ForeColor = System.Drawing.SystemColors.HotTrack;
         this.UPDOWN_DOMAIN.Location = new System.Drawing.Point(24, 40);
         this.UPDOWN_DOMAIN.Name = "UPDOWN_DOMAIN";
         this.UPDOWN_DOMAIN.Size = new System.Drawing.Size(232, 26);
         this.UPDOWN_DOMAIN.Sorted = true;
         this.UPDOWN_DOMAIN.TabIndex = 5;
         this.UPDOWN_DOMAIN.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
         this.UPDOWN_DOMAIN.UpDownAlign = System.Windows.Forms.LeftRightAlignment.Left;
         this.UPDOWN_DOMAIN.Wrap = true;
         // 
         // label1
         // 
         this.label1.Location = new System.Drawing.Point(24, 16);
         this.label1.Name = "label1";
         this.label1.Size = new System.Drawing.Size(136, 23);
         this.label1.TabIndex = 9;
         this.label1.Text = "UpDownDomain Control";
         // 
         // UpDown
         // 
         this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
         this.ClientSize = new System.Drawing.Size(344, 117);
         this.Controls.AddRange(new System.Windows.Forms.Control[] {
                                                                      this.label1,
                                                                      this.UPDOWN_DOMAIN,
                                                                      this.button1,
                                                                      this.button2,
                                                                      this.textBox1});
         this.Name = "UpDown";
         this.Text = "UpDownDomain Control";
         this.Load += new System.EventHandler(this.UpDown_Load);
         this.ResumeLayout(false);

      }
        #endregion

        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main() 
        {
            Application.Run(new UpDown());
        }

        private void UpDown_Load(object sender, System.EventArgs e)
        {
            // Populate the UpDown Domain control with string objects
            UPDOWN_DOMAIN.Items.Add("Visual C#");
            UPDOWN_DOMAIN.Items.Add("Visual C++");
            UPDOWN_DOMAIN.Items.Add("Visual VB");
            UPDOWN_DOMAIN.Items.Add("Managed C++");
            UPDOWN_DOMAIN.Items.Add("Crystal Reports");
            UPDOWN_DOMAIN.Items.Add("MFC");
            UPDOWN_DOMAIN.Items.Add("ATL");
            UPDOWN_DOMAIN.Items.Add("COM");
            UPDOWN_DOMAIN.Items.Add("DCOM");
            UPDOWN_DOMAIN.Items.Add("COM+");
            UPDOWN_DOMAIN.Items.Add("SETUP");
            UPDOWN_DOMAIN.Items.Add("COMMAND LINE");
            UPDOWN_DOMAIN.Items.Add("WINDOWS SERVICE");
            UPDOWN_DOMAIN.Items.Add("WINDOWS LIBRARY");
            UPDOWN_DOMAIN.Items.Add("ASP .NET WEB");
            UPDOWN_DOMAIN.Items.Add("DATABASE APPLICATION");

        }

        private void button1_Click(object sender, System.EventArgs e)
        {
            // Select the Item that want to remove
            int nItemSel = UPDOWN_DOMAIN.SelectedIndex;
            if ( nItemSel >= 0 ) 
            {
                // Remove the item at the location
                UPDOWN_DOMAIN.Items.RemoveAt(nItemSel);
                // Update the control
                UPDOWN_DOMAIN.Update();
                // Clear the edit box
                UPDOWN_DOMAIN.Text = "" ; 
            }
        }

        private void button2_Click(object sender, System.EventArgs e)
        {
            if ( textBox1.Text == "" ) 
            {
                MessageBox.Show("Enter a string to add");
                return ;
            }
            // Add the new string the UpDownDomain control
            UPDOWN_DOMAIN.Items.Add(textBox1.Text);
            textBox1.Text = "" ; 
        }


    }
}


           
          


String based DomainUpDown (Spinner)


   


  using System;
  using System.Drawing;
  using System.Collections;
  using System.ComponentModel;
  using System.Windows.Forms;
  using System.Data;

  public class UpDownForm : System.Windows.Forms.Form
  {
    private System.Windows.Forms.Label lblCurrSel;
    private System.Windows.Forms.Button btnGetSelections;
    private System.Windows.Forms.Label label1;
    private System.Windows.Forms.DomainUpDown domainUpDown;

    public UpDownForm()
    {
      InitializeComponent();
    }

    private void InitializeComponent()
    {
      this.label1 = new System.Windows.Forms.Label ();
      this.domainUpDown = new System.Windows.Forms.DomainUpDown ();
      this.btnGetSelections = new System.Windows.Forms.Button ();
      this.lblCurrSel = new System.Windows.Forms.Label ();

      label1.Location = new System.Drawing.Point (8, 24);
      label1.Text = "Domain UpDown Control";
      label1.Size = new System.Drawing.Size (224, 32);
      label1.Font = new System.Drawing.Font ("Verdana", 12);
      label1.TabIndex = 2;

      domainUpDown.Location = new System.Drawing.Point (264, 24);
      domainUpDown.Text = "domainUpDown1";
      domainUpDown.Size = new System.Drawing.Size (168, 20);
      domainUpDown.TabIndex = 0;
      domainUpDown.Sorted = true;
      domainUpDown.Wrap = true;
      domainUpDown.SelectedItemChanged += new System.EventHandler (this.domainUpDown_SelectedItemChanged);
      domainUpDown.Items.AddRange(new object[4] {"B", "A", "C", "(D)"});
      btnGetSelections.Location = new System.Drawing.Point (16, 136);
      btnGetSelections.Size = new System.Drawing.Size (136, 24);
      btnGetSelections.TabIndex = 4;
      btnGetSelections.Text = "Get Current Selections";
      btnGetSelections.Click += new System.EventHandler (this.btnGetSelections_Click);

      lblCurrSel.Location = new System.Drawing.Point (176, 120);
      lblCurrSel.Size = new System.Drawing.Size (256, 48);
      this.Text = "Spin Controls";
      this.AutoScaleBaseSize = new System.Drawing.Size (5, 13);
      this.ClientSize = new System.Drawing.Size (448, 181);
      this.Controls.Add (this.lblCurrSel);
      this.Controls.Add (this.btnGetSelections);
      this.Controls.Add (this.label1);
      this.Controls.Add (this.domainUpDown);
    }
    static void Main() 
    {
      Application.Run(new UpDownForm());
    }

    protected void domainUpDown_SelectedItemChanged (object sender, System.EventArgs e)
    {
      this.Text = "You changed the string value...";
    }

    protected void btnGetSelections_Click (object sender, System.EventArgs e)
    {
      // Get info from updowns...
      lblCurrSel.Text = "String: " 
        + domainUpDown.Text ;
    }
  }