VB6 beginners tutorial - Learn VB6

Advanced VB6 tutorial - Learn Advanced VB6

VB .NET - Learn Visual Basic .NET

Systems Analysis - System analysis and Design tutorial for Software Engineering

Browse Topics

- Getting started
- Data Types
- Modules
- Operators in VB6
- VB6 Variable
- VB6 Procedures
- VB6 Control Structures
- Loops in VB6
- VB6 Exit Do & With End With
- Arrays in VB6
- User-Defined Data Types
- VB6 Constants
VB6 Built-in Functions
- Date and Time in VB6
- VB6 Controls
- TextBox Control
- ComboBox & OptionButton
- Label & Frame
- PictureBox & ImageBox
- Timer Control
- ListBox & ComboBox
- VB6 ScrollBar
- Control Arrays in VB6
- Files controls in VB6
- VB6 CheckBox
- Forms in VB6
- Menus in VB6
- MDI Form in VB6
- InputBox
- MessageBox
- Mouse events
- Mouse Move
- Error Handling
Error Handling (2)
VB6 Database

You are here: Visual Basic > VB6 (Beginners Tutorial)

Tutorial Main Page | Previous Page | Contents | Next Page

User-Defined Variables

• Data used with random access files is most often stored in user-defined variables. These data types group variables of different types into one assembly with a single, user-defined type associated with the group. Such types significantly simplify the use of random access files.

• The Visual Basic keyword Type signals the beginning of a user-defined type declaration and the words End Type signal the end. An example best illustrates establishing a user-defined variable. Say we want to use a variable that describes people by their name, their city, their height, and their weight. We would define a variable of Type Person as follows:

Type Person
Name As String
City As String
Height As Integer
Weight As Integer
End Type

These variable declarations go in the same code areas as normal variable declarations, depending on desired scope. At this point, we have not reserved any storage for the data. We have simply described to Visual Basic the layout of the data.

• To create variables with this newly defined type, we employ the usual Dim statement. For our Person example, we would use:

Dim Lou As Person
Dim John As Person
Dim Mary As Person

And now, we have three variables, each containing all the components of the variable type Person. To refer to a single component within a user-defined type, we use the dot-notation:


As an example, to obtain Lou’s Age, we use:

Dim AgeValue as Integer
AgeValue = Lou.Age

Note the similarity to dot-notation we’ve been using to set properties of various Visual Basic tools.


Tutorial Main Page | Previous Page | Contents | Next Page


Home | About Us | Privacy Policy | Contact Us

Copyright © | All Rights Reserved