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Unit 6: VB Control Structure

encountered, the entire process is repeated, beginning with the testing of condition in the Do
While statement. In other words, the statements inside the loop are repeatedly executed only as
long as (that is, while) the condition is true. Figure 6.2 contains the pseudocode and flowchart
for this loop.

In the No
condition
true ?

Yes

Execute
Do while condition is true statements
processing step (s) within
Loop the loop

Execute
statements
that follow
the loop

Figure 6.2: Pseudocode and Flowchart for a Do While Loop.
1: The following program, in which the condition in the Do loop is “num
<=7”, displays the numbers from 1 through 7. (After the Do loop executes,
the value of num will be 8.)
Private Sub btnDisplay_Click(...) Handles btnDisplay.Click
‘Display the numbers from 1 to 7
Dim num AsInteger = 1
DoWhile num <= 7
lstNumbers.Items.Add(num)
num += 1 ‘Add 1 to the value of num
Loop
End Sub
[Run, and click the button. The following is displayed in the list box.]
1
2
3
4
5
6
7

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