RadioButton control provides a round interface to select one option from a
number of options. Radio buttons are usually placed in a group on a container
control such as a Panel or a GroupBox and one of them is selected.
Creating a RadioButton
We can create a RadioButton control using a
Forms designer at design-time or using the RadioButton class in code at run-time
(also known as dynamically).
To create a RadioButton control at design-time,
you simply drag and drop a RadioButton control from Toolbox to a Form in Visual
Studio. After you drag and drop a RadioButton on a Form, the RadioButton looks
like Figure 1. Once a RadioButton is on the Form, you can move it around and
resize it using mouse and set its properties and events.
Creating a RadioButton control at
run-time is merely work of creating an instance of RadioButton class, set its
properties and add RadioButton class to the Form controls.
First step to create a dynamic
RadioButton is to create an instance of RadioButton class. The following code
snippet creates a RadioButton control object.
In the next step, you may set
properties of a RadioButton control. The following code snippet sets location,
width, height, background color, foreground color, Text, Name, and Font
properties of a RadioButton.
dynamicRadioButton.Left = 20
dynamicRadioButton.Top = 100
dynamicRadioButton.Width = 300
dynamicRadioButton.Height = 30
"I am a Dynamic RadioButton"
Once a RadioButton control is ready with its properties,
next step is to add the RadioButton control to the Form. To do so, we use
Form.Controls.Add method. The following code snippet adds a RadioButton control
to the current Form.
New RadioButton created by the above code looks like Figure
Setting RadioButton Properties
place a RadioButton control on a Form, the next step is to set properties.
way to set properties is from the Properties Window. You can open Properties
window by pressing F4 or right click on a control and select Properties menu
item. The Properties window looks like Figure 3.
Location, Height, Width, and Size
The Location property takes a Point
that specifies the starting position of the RadioButton on a Form. You may also
use Left and Top properties to specify the location of a control from the left
top corner of the Form. The Size property specifies the size
of the control. We can also use Width and Height property instead of Size
property. The following code snippet sets Location, Width, and Height properties
of a RadioButton control.
dynamicRadioButton.Height = 40
dynamicRadioButton.Width = 300
Background, Foreground, BorderStyle
ForeColor properties are used to set background and foreground color of a
RadioButton respectively. If you click on these properties in Properties window,
the Color Dialog pops up.
Alternatively, you can set background and foreground colors at run-time. The
following code snippet sets BackColor and ForeColor properties.
Name property represents a unique name
of a RadioButton control. It is used to access the control in the code. The
following code snippet sets and gets the name and text of a RadioButton control.
Text property of a RadioButton
represents the current text of a RadioButton control. The TextAlign property
represents text alignment that can be Left, Center, or Right. The following code
snippet sets the Text and TextAlign properties and gets the size of a
"I am a Dynamic RadioButton"
Font property represents the font of
text of a RadioButton control. If you click on the Font property in Properties
window, you will see Font name, size and other font options. The following code
snippet sets Font property at run-time.
way of reading a RadioButton control contents is using the Text property. The
following code snippet reads contents of a RadioButton in a string.
String = dynamicRadioButton.Text
property of RadioButton can be used to set the appearance of a RadioButton to a
Button or a RadioButton. The Button look does not have a round select option.
The following property makes a RadioButton look like a Button control.
Check Mark Alignment
property is used to align the check mark in a RadioButton. By using CheckAlign
and TextAlign properties, we can place text and check mark to any position on a
RadioButton we want. The following code snippet aligns radio button round circle
and text to middle-right and creates a RadioButton that looks like Figure 4.
character (...) is used to give an impression that a control has more characters
but it could not fit in the current width of the control. If AutoEllipsis
property is true, it adds ellipsis character to a control if text in control
does not fit. You may have to set AutoSize to false to see the ellipses
character. The following code snippet sets the AutoEllipsis property of a
RadioButton to true.
dynamicRadioButton.AutoEllipsis = True
Figure 5 shows
a RadioButton when AutoEllipsis is true and contents does not fit in the given
width of the control.
Image in RadioButton
property of a
RadioButton control is used to set the background as
an image. The Image property needs an Image object. The Image class has a static
method called FromFile that takes an image file name with full path and creates
an Image object.
also align image and text. The ImageAlign and TextAlign properties of
RadioButton are used for this purpose.
code snippet sets an image as a
A typical RadioButton control has two possible states â€" Checked
and Unchecked. Checked state is when the RadioButton has check mark on and
Unchecked is when the RadioButton is not checked. Typically, we use a mouse to
check or uncheck a RadioButton.
Checked property is true when a RadioButton is in checked state.
Usually, we check if a RadioButton is checked or not and decide to
take an action on that state something like following code snippet.
AutoCheck property represents
whether the Checked or CheckState values and the RadioButton's appearance are
automatically changed when the RadioButton is clicked. By default this property
is true but if set to false.
RadioButton Checked Event Hander
CheckedChanged event occurs
when the value of the Checked property changes. To add this event handler, you
go to Events window and double click on CheckedChanged events as you can see in
code snippet defines and implements these events and their respective event
handlers. You can write this code to implement CheckedChanged event dynamically.
sender As System.Object,
ByVal e As
article, we discussed discuss how to create a RadioButton control in Windows
Forms at design-time as well as run-time. After that, we saw how to use various
properties and methods.