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05 Data types / variables
VB,
Like
most programming languages, stores information
In
multiple
formats. The basic
Data
types supported by VB are:
'Integer whole numbers -32,768 to +32,767 2 bytes
'Long whole numbers -2,147,483,648 to +2,147,483,647 4 bytes
'Single numbers with decimal points -1.4E-45 to +3.4E38 4 bytes
'Double numbers with decimal points -4.9E-324 to 1.8E308 8 bytes
'Boolean value of True or False only
'Strings sequences of characters, such as "abc123"
'Byte single character 0 to 255
'Date includes date and time
'Variant any type from the list above
'Variables are names assigned to store values. Variable naming rules are:
'1. Start with a letter
'2. Consist of letter, numbers, or an underscore '_'
'3. Cannot exceed 255 characters
'To create a variable of a certain type, use the Dim function
Dim
MyString
As
String
MySring
=
"abc"
Dim
Y
As
Integer
Y
=
2
'VB also supports a user-defined type (UDT), which is a combination
'of the other types
Type
Address
Address
As
String
City
As
String
State
As
String
Zip
As
String
End
Type
Dim
R
As
Address
R.Address
=
"101 Clover Lange"
R.City
=
"Tulsa"
R.State
=
"OK"
R.Zip
=
"72310"
'These VB function are available to convert 1 data type into another
Cbool
(expression)
CByte
(expression)
CCur(expression)
CDate
(expression)
CDbl
(expression)
CDec
(expression)
CInt
(expression)
CLng
(expression)
CSng
(expression)
CStr
(expression)
CVar(expression)
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