A
MaskedTextBox control provides validation mechanism for user input on a Form.
For example, if you want a TextBox to accept date in mm/dd/yyyy format, you can
set masking in the MaskedTextBox.
In this
article, I will discuss how to create a MaskedTextBox control in Windows Forms
at design-time as well as run-time. After that, I will continue discussing
various properties and methods available for the MaskedTextBox control.
Creating a MaskedTextBox
We can create a MaskedTextBox control using a
Forms designer at design-time or using the MaskedTextBox class in code at
run-time (also known as dynamically).
To create a MaskedTextBox control at
design-time, you simply drag and drop a MaskedTextBox control from Toolbox to a
Form in Visual Studio. After you drag and drop a MaskedTextBox on a Form, the
MaskedTextBox looks like Figure 1. Once a MaskedTextBox is on the Form, you can
move it around and resize it using mouse and set its properties and events.
Figure 1
Creating a MaskedTextBox control at
run-time is merely a work of creating an instance of MaskedTextBox class, set
its properties and add MaskedTextBox class to the Form controls.
First step to create a dynamic
MaskedTextBox is to create an instance of MaskedTextBox class. The following
code snippet creates a MaskedTextBox control object.
Dim
dynamicMaskedTextBox As
New
MaskedTextBox()
In the next step, you may set
properties of a MaskedTextBox control. The following code snippet sets
background color, foreground color, Text, Name, and Font properties of a
MaskedTextBox.
dynamicMaskedTextBox.BackColor =
Color.Red
dynamicMaskedTextBox.ForeColor =
Color.Blue
dynamicMaskedTextBox.Text =
"I am Dynamic MaskedTextBox"
dynamicMaskedTextBox.Name =
"DynamicMaskedTextBox"
dynamicMaskedTextBox.Font =
New
Font("Georgia", 16)
Once a MaskedTextBox control is ready with its properties,
next step is to add the MaskedTextBox control to the Form. To do so, we use
Form.Controls.Add method. The following code snippet adds a MaskedTextBox
control to the current Form.
Controls.Add(dynamicMaskedTextBox)
Setting MaskedTextBox Properties
After you
place a MaskedTextBox control on a Form, the next step is to set properties.
The easiest
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 2.
Figure 2
Location, Height, Width, and Size
The Location property takes a Point
that specifies the starting position of the MaskedTextBox on a 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 MaskedTextBox control.
dynamicMaskedTextBox.Location =
New
Point(20, 150)
dynamicMaskedTextBox.Height = 40
dynamicMaskedTextBox.Width = 300
Background, Foreground, BorderStyle
BackColor and
ForeColor properties are used to set background and foreground color of a
MaskedTextBox 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.
dynamicMaskedTextBox.BackColor =
Color.Red
dynamicMaskedTextBox.ForeColor =
Color.Blue
You can also
set borders style of a MaskedTextBox by using the BorderStyle property. The
BorderStyle property is represented by a BorderStyle enumeration that has three
values â€" FixedSingle, Fixed3D, and None. The default value
of border style is Fixed3D. The following code snippet sets the border style of
a MaskedTextBox to FixedSingle.
dynamicMaskedTextBox.BorderStyle =
BorderStyle.FixedSingle
Name
Name property represents a unique name
of a MaskedTextBox control. It is used to access the control in the code. The
following code snippet sets and gets the name and text of a MaskedTextBox
control.
dynamicMaskedTextBox.Name =
"DynamicMaskedTextBox"
Text, TextAlign, and TextLength
Text property of a MaskedTextBox
represents the current text of a MaskedTextBox control. The TextAlign property
represents text alignment that can be Left, Center, or Right. The TextLength
property returns the length of a MaskedTextBox contents.
The following code snippet sets the
Text and TextAlign properties and gets the size of a MaskedTextBox control.
dynamicMaskedTextBox.Text =
"I am Dynamic MaskedTextBox"
dynamicMaskedTextBox.TextAlign
= HorizontalAlignment.Center
Font
Font property represents the font of
text of a MaskedTextBox 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.
dynamicMaskedTextBox.Font =
New
Font("Georgia", 16)
Maximum Length
You can
restrict number of characters in a MaskedTextBox control by setting MaxLength
property. The following code snippet sets the maximum length of a MaskedTextBox
to 50 characters.
dynamicMaskedTextBox.ReadOnly =
True
dynamicMaskedTextBox.MaxLength = 50
Masking Related Properties
Mask
Mask the
default property and represents the format of the input can be accepted by a
control. We can set Mask property by clicking on the control and click on the
little handler and select Set Mask link as you can see in Figure 3.
Figure 3
Set Mask
launches Input Mask dialog where we can select a mask and you can see its data
format and also set the validation type. See Figure 4.
Figure 4
The following
code snippet sets the Mask property at run-time.
dynamicMaskedTextBox.Mask =
"00/00/0000"
Here is a list
and description of masking characters.
- 0 â€"
Digit, required. Value between 0 and 9.
- ·
9
â€" Digit or space, optional.
- ·
# -
Digit or space, optional. If this position is
blank in the mask, it will be rendered as a space in the Text property.
- ·
L -
Letter, required. Restricts input to the ASCII
letters a-z and A-Z.
- ·
? -
Letter, optional. Restricts input to the ASCII
letters a-z and A-Z.
- ·
& - Character, required.
- ·
C - Character, optional. Any non-control
character.
- ·
A - Alphanumeric, required.
- ·
a - Alphanumeric, optional.
- ·
. - Decimal placeholder.
- ·
, - Thousands placeholder.
- ·
: - Time separator.
- ·
/ - Date separator.
- ·
$ - Currency symbol.
- ·
< - Shift down. Converts all characters that
follow to lowercase.
- ·
> - Shift up. Converts all characters that
follow to uppercase.
- ·
| - Disable a previous shift up or shift down.
- ·
\ - Escape. Escapes a mask character, turning it
into a literal. "\\" is the escape sequence for a backslash.
- ·
All other characters - Literals. All non-mask
elements will appear as themselves within MaskedTextBox. Literals always
occupy a static position in the mask at run time, and cannot be moved or
deleted by the user.
MaskFull
MaskFull
property represents if the mask values are completed.
If
(MaskedTextBox1.MaskFull) Then
End
If
BeepOnError
If set true,
the system beep is generated when incorrect values are entered.
dynamicMaskedTextBox.BeepOnError =
True
Summary
A
MaskedTextBox control accepts user input on a Form. In this article, we
discussed discuss how to create a MaskedTextBox control in Windows Forms at
design-time as well as run-time. After that, we saw how to use various
properties and methods.