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Unit 6: VB Control Structure

6.7 Summary

• Loop is one of the most important structure in visual basic, as it repeats a sequence of
statement either as long as until a certain condition is true.

• Do-while loops repeat the sequence of statement as long as or until certain condition is true.
• Next loops are easy to reaed and write and also have features that make them ideal for
certain common tasks.

6.8 Keywords

Do loops: It repeats a sequence of statements either as long as or until a certain condition is true
Else If clauses: An extension of the If block allows for more than two possible alternatives with
the inclusion of ElseIf clause
If block: If block allows a program to decide on course of action based on a course of action based
on whether certain conditions are true or false.
Loop: A loop, one of the most important structures in Visual Basic, is used to repeat a sequence
of statements a number of times.
User-Defined Type (UDT): In previous versions of Visual Basic a Structure was called a user-
defined type (UDT).
While Wend statement: The While Wend statement repeats a block of code while a condition is
true. The condition is always evaluated before entering the loop. If it is not fulfilled, the loop
is never executed.

Write a program using if-else statement.

6.9 Self Assessment Questions
1. In general, a Structure type is defined by:

(a) Structure block of the form (b) Structure block of pixel
(c) Structure block of the image (d) None of the above.
2. Visual Basic a Structure was called as a user-defined type (UDT).
(a) True (b) False
3. Subvariables of the Structure type is called a………………
(a) sub member (b) group
(c) member (d) none
4. An ……….. allows a program to decide on a course of action based on whether certain
conditions are true or false.
(a) If-else (b) If block
(c) For—next loop (d) Do while loops

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