Check that all values in one array are part of another

Question

I’m working with this code

if(in_array($_GET['a'], array('value1', 'value2', 'value3'))) {
    [...]
}

It serves to check whether $_GET['a'] this inside the array.

I’m trying to pass the values value1,value2,value3 in $_GET['a'] to "check" these values in the array, if all exist it executes my code => [...]

Answer 1

If I understand the question correctly, and if you really have equal arrays at both ends, you can use the operator ==. He will return true when both arrays have the same keys and values:

array('a' => 10, 'b' => 20) == array('b' => 20, 'a' => 10)

In this example with explicit keys, order is not important. But as in your example the keys are implicit (numerical), you need to sort the arrays first. The example still considers that the input arrives as string separated by commas, as you commented:

$entrada = sort(explode($_GET['a']));
$referencia = sort(array('value1', 'value2', 'value3'))
if($entrada == $referencia) ...

^{See a test}

In that case, you can also use ===, that requires values in arrays to have the same keys and types in the same order (these last two conditions do not apply to ==).

Already the in_array when you receive an array as the first parameter, check whether anyone of its values is contained in the other, and not if all are contained therein (see example in the manual).

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Reference: Manual for PHP - Array Operators

Answer 2

You can use array_diff to calculate the difference and consider the same or no array.

Being his inputA a string, just use explode to transform into an array and compare the items into arrays. Note that the array order nay influences the result. I put an example in Ideone with 2 cases.

When there is a difference, the output will be an array with key and value array[3]=>value999, if they are equal, even in a different order, the output will be a empty array.

$inputA = explode( ', ' , 'value1, value2, value3, value999' );
$arrays = array( 'value3', 'value1', 'value2' );
print_r( array_diff( $inputA , $arrays ) );

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DOC: array_diff( array $array1 , array $array2 [, array $ ... ] )

Returns a array containing all array1 entries that are not present in any of the other arrays.