Do... While Loop Statement:
Repeats a block of statements
while a condition is True or until a condition becomes True.
Syntax:
Do [{While | Until} condition]
[statements]
[Exit Do]
[statements]
Or, you can use this syntax:
Do
[statements]
[Exit Do]
[statements]
Loop [{While | Until} condition]
The Do Loop statement syntax has these
parts:
Part
|
Description
|
condition
|
Optional. Numeric expression or string expression that is True or False. If condition is Null, condition is
treated as False.
|
statements
|
One or more statements that are repeated while, or until, condition is True.
|
Remarks:
Any number of Exit Do statements may be placed anywhere in the Do…Loop
as an alternate way to exit a Do…Loop.Exit Do is often used after
evaluating some condition, for example, If…Then, in which case the Exit
Do statement transfers control to the statement immediately following the Loop.
When used within nested Do…Loop statements, Exit Do
transfers control to the loop that is one nested level above the loop where Exit
Do occurs.
Example:
This example shows how Do...Loop statements can be used. The
inner Do...Loop statement loops 10 times, sets the value of the flag to False,
and exits prematurely using the Exit Do statement. The outer loop exits
immediately upon checking the value of the flag.
Dim
Check, Counter Check = True: Counter = 0 ' Initialize variables. Do ' Outer loop. Do While Counter < 20 ' Inner loop. Counter = Counter + 1 ' Increment Counter. If Counter = 10 Then ' If condition is True. Check = False ' Set value of flag to False. Exit Do ' Exit inner loop. End If Loop Loop Until Check = False ' Exit outer loop immediately. |
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