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Unit 7: Introduction to ASP (Active Server Pages)
The If...Then Statement Notes
The simplest technique used to validate a condition is to check whether it is true. This can be
done using an If...Then statement. The formula to use is:
If ConditionToCheck is True Then Statement
The program examines a condition, in this case ConditionToCheck. This ConditionToCheck can
be a simple expression or a combination of expressions. If the ConditionToCheck is true, then
the program will execute the Statement.
There are two ways you can use the If...Then statement. If the conditional formula is short
enough, you can write it on one line, like this:
If ConditionToCheck is True Then Statement
If there are many statements to execute as a truthful result of the condition, you should write the
statements on alternate lines. Of course, you can use this technique even if the condition you are
examining is short.
Notes In this case, one very important rule to keep is to terminate the conditional statement
with End If.
The formula used is:
If ConditionToCheck is True Then
Statement
End If
The If...Then...Else Statement
The If...Then statement offers only one alternative: to act if the condition is true. Whenever you
would like to apply an alternative in case the condition is false, you can use theIf...Then...Else
statement. The formula of this statement is:
If ConditionToCheck is True Then
Statement1
Else
Statement2
End If
When this section of code executes, if the ConditionToCheck is true, then the first
statement,Statement1, is executed. If the ConditionToCheck is false, the second statement, in
this
caseStatement2, is executed.
The If...Then...ElseIf Statement
The If...Then...ElseIf statement acts like the If...Then...Else expression, except that it offers as
many choices as necessary. The formula to use is:
If Condition1 is True Then
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