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PHP PHP Arrays and Control Structures PHP Loops While Listing Array Values

Hey There
Hey There
3,086 Points
Posted by Hey There
Hey There
3,086 Points

Why does this loop run twice?

I thought this loop should run only once since the first round $count++ makes the value to become 1 which is <2. But the second time $count++ becomes 2 which is not <2 anymore. But why are there 2 results in the output?

$learn = array('Conditionals','Arrays','Loops'); $learn[] = 'Build something awesome!'; array_push($learn,'Functions','Forms','Objects'); array_unshift($learn,'HTML','CSS'); asort($learn);

$count = 0; while ((list($key, $val) = each($learn)) && $count++ <2) { echo "$key => $val\n"; }

OUTPUT:

3 => Arrays
5 => Build something awesome!

1 Answer

Robert Anthony
Robert Anthony
19,952 Points
Robert Anthony
Robert Anthony
19,952 Points

$count++ < 2

This checks that the value of $count is less than 2 (it is because it is 0) and then the ++ increases it by one. Then on the second loop, the value of $count is 1, so it is less than 2 and the ++ increases it by one.

This is why the loop executes twice. You can fix this either by changing the test to $count < 1 OR ++$count < 2. The second one here increments $count BEFORE doing the test. However, the first fix is clearer.