I have searched the site for a question that is the same or similar, but I cannot find what I am looking for. Perhaps this is because my question is somewhat strange or unlogical (but I hope you'll be able to clear that up).

Here's the case: I have a function to test to see if something is not in an array. I have to make absolutely sure this function returns only true if what I look for is not in the array. I have recreated a simplified function so you understand what I mean. In this function I want to make sure there is not any 'A' in my array, one or more.

'A'

$array = ["A", "F", "B", "G"]

function check($array) {
$noAs = false;
$n = 0;

foreach ($array as $letter) {
if ($letter == "A") {
$n++;
}
}

if ($n == 0) {
$noAs = true;
};

return $noAs;
}


I then can show the result:

if (check($array) == true) {
echo "the are no A's";
} else {
echo "there are A's";
}


The above function work fine, but as you can see with $noAs = true; I, by default, set the return value to true. My fear is, that if by some server error the function is not executed properly, the function will return true even though there are A's in my array. Am I making sense or is this never gonna happen?

$noAs = true;

In order to set the default $noAs = false; I created this function which also works:

$noAs = false;

function check2($array)
{
$noAs = false;
$n = 0;

foreach ($array as $letter) {
if ($letter == "A") {
$n++;
}
}

if ($n == 0) {
$noAs = true;
}$array = ["A", "F", "B", "G"];

return $noAs;
}


So my question is, was it wise to have created this second function instead of the first one, or does it really not matter at all?

is_array()

in_array()

return count(array_filter($array, function($e) { return $e === "A"; })) === 0;

is_array()

1 Answer
1

To answer your worries first. No there will be no point where a server error can cause your function return the opposite of expected result, as long as "A" is inside your array.

However, you seem to have done way too much coding for something that already exists.

You should use in_array:

$array = ["A", "F", "B", "G"]
if( in_array( "A", $array ) ) {
// Do stuff
} else {
// Do something else
}


If you want it to be case insensitive:

$array = ["A", "F", "B", "G"]
if( in_array( strtolower("A"), array_map('strtolower', $array) ) ) {
// Do stuff
} else {
// Do something else
}


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