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The loop Do Until allow to execute a block of instructions between the two keywords Do Until and Loop a number of times. The difference from the for loop is in the exit condition. Here the exit condition is a Boolean expression which is evaluated at every loop. If the condition is True then the loop stops.
The syntax is the following:
Do Until (Boolean Expression)
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"Block of instructions"
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Loop
In this loop is possible to exit earlier, using the same technique seen in the For loop. Inserting the instruction "Goto Label" inside a Do Until loop, where Label is a line of code after the keyword Loop.
Let's see and example:
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bFound = False
Do Until (I > 30)
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If (bFound = True) Then
Goto ExitDoLoop
EndIf
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Loop
ExitDoLoop:
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Inside For or Do Until loops, there can be also other nested loops.
Do Until (I > 30)
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Do Until (A + 1 > 20)
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Loop
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Loop
Here there are no indexes so the exit condition is exactly the same at every passage, unlike in the For loop.
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