The Output:
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Adding
Controls to Forms:
The Windows
Forms framework summarize native Win32 APIs and exposes
secure, managed classes for creating Win32 client-side
applications. The Windows Forms class library offers a
lot of controls such as buttons, check boxes, drop-down
lists, combo boxes, data grid, and other client-side
functionality.
To add controls
in the form the First step is declare the required
private member variables. After that configure the look
of each control in the Form's constructor or in the
IntializeComponent () method using properties, methods
and events. Finally add the controls to the Form's
controls collection using control property.
Now let us see
an example program Formexample:
In this example
as I said previously, first I declare the private Button
btncont,& TextBox TBox member variable. Then I
constitute the Properties of the Button control,TextBox
control in the InitializeComponent(). Then I build a
delegate for the click event of a button. The argument
to the constructor contains a reference to the method
that performs the event handling logic.The btncont.Click
+ = handler registers the delegate with the Click event
of the button.The Form class has a Controls property
that is a collection of child controls. The Add method
adds your control to that collection.
The
example: Formexample.VB
Imports System
Imports
System.ComponentModel
Imports
System.WinForms
Imports
System.Drawing
Public
Class
Formexample
Inherits Form
Private
btncont As
New
Button()
Private
TBox As
New
TextBox()
Sub
New()
InitializeComponent()
End
Sub
'New
Private
Sub
InitializeComponent()
Dim
handler As
New
EventHandler(btncontClick)
btncont.Text = "Click Me!!"
btncont.Anchor = AnchorStyles.TopLeft
btncont.Click += handler
TBox.Location =
New
Point(85, 0)
TBox.Size =
New
Size(150, 50)
TBox.TabIndex = 1
ClientSize =
New
Size(250, 250)
Me.Controls.Add(btncont)
Me.Controls.Add(TBox)
End
Sub
'InitializeComponent
Private
Sub
btncontClick(ByVal
sender As
Object,
ByVal
e As
EventArgs)Me.BackColor
= Color.IndianRed
TBox.Text = "You Click the Button[Arungg]"
TBox.BackColor = Color.Cyan
End
Sub
'btncontClick
'Entry
point which delegates to C-style main Private Function
Public
Overloads
Shared
Sub
Main()
Main(System.Environment.GetCommandLineArgs())
End
Sub
Public
Overloads
Shared
Sub
Main(ByVal
args() As
String)
Application.Run(New
Formexample)
End
Sub
'Main
End
Class
'Formexample
VBC /r:System.WinFOrms.dll
/r:System.dll /r:Microsoft.Win32.Interop.dll /r:System.Drawing.dll
Formexample.VB
The Output:
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In another way by using a rapid
application development (RAD) environment such as Visual
Studio.NET the application development is very much
simplified. In the Visual Studio Windows Forms designer,
the controls appear in a toolbox and are dropped on a
design surface. This is accompanied by automatic code
generation.
The forms designer has a
property window that displays properties and events.
Every Windows Forms application is a class that derives
from System.WinForms.Form. invokes the Run method of the
System.WinForms.Application class in its Main method,
with an instance of the form as the argument. The
Application.Run method processes messages from the
operating system to the application.