What is Variables?
If you have never programmed before, you may wonder what the
term variable means. A variable is a small section of a
computer's memory that you give a name to.
Data Types
There many different type of data that you might want to be
able to store into a variable: numbers, words, dates, and many
more.
Integer
An integer is a whole number - that is, a number with no
fractional portion. For Example 1, 7, 9 and -5 are all integer,
but 2.1, 0.3, and -6.1 are not. Two other data types are related
to the integer: bytes and long. A long can store larger range of
number than an integer. A byte store fewer.
Floating-point number may have a decimal. 1.5, -3.4,
4.3 and even 5.0 are all floating points numbers. It is important to
note, however, that although integers are stored exactly, that is
not necessarily true of floating-point numbers. Floating-point
numbers are often rounded or truncated to fit into the space
allotted for them.
A String can hold any sequence of letters, numbers,
and symbols. Strings are distinguished from code, variable name, and
numbers by putting them between double quotation marks.
"My name is Adi", "20kph", and "2008"
These are all possible strings. Even the empty string " " can be
treated like a string in most case.
Date
A nice feature of VBScript that is missing in other programming
languages is its date handling. Although it is possible to represent
the date using string and /or integers, this variable type
simplifies thing. A date variable can hold either a date or time,
and VBScript's various date functions and operators make the
formatting and printing of date related information easily.
Boolean
A Boolean variable may hold a value of either True or False. Boolean
variables are generally used when a decision needs to be made. The
value of variable can determine which of two actions should be
taken.
What does it meant to Declare a Variable ?
Many programming language requires that, before you use a variable
of different types of data you intent to put into the variable and
what you want it to be called. For example, in the C++ programming
language, you might say
int my_variable;
my_variable = 2;
The first line tells system that you want to use a variable that you
will call my_variable, an that you want to be able to put integer
data into it.
Declaring Variables with Option Explicit
<%@ Language=VBScript %>
<% Option Explicit %>
<% Dim myfirstvariable
myfirstvariable = 2%>
<HTML>
<BODY> The Variable named "myfirstvariable" has a value of
<%
Response.Write(myfirstvariable)
%>
</BODY>
</HTML>
