Changing the way PHP in_array does object comparison

Question

I am working on using in_array() to check if a Course object called (appropriately named) Course is in an array.

One issue I am having is, I want to use a specific property within my Course object to do the object comparison, instead of comparison of the entire object.

Specifically, I want to use the $course->getShortName() to do the comparison. Why? Because all the other private variables within my Course object can be different, except for the short_name property which can stay the same, and that's why I want to use it to do the object property.

Method that does the comparison:

public function overlap($courses, $course_temp) {
    for ($i = 0; $i < count($courses); $i = $i + 1) {
        if ($this->overlapCourses($courses[$i], $course_temp)) {
            // Push the class that is conflicted to the conflictedClass
            // array
            // TODO: Figure out why it's being added to the list
            if(!in_array($courses[$i], $this->conflictClasses)) {
                array_push($this->conflictClasses, $courses[$i]);
            }

            // Push the class that is conflicted with to the
            // conflictedClass array
            // TODO: Figure out why it's being added to the list
            if(!in_array($course_temp, $this->conflictClasses)) {
                array_push($this->conflictClasses, $course_temp);
            }
            return false;
        }
    }
    return false;
}

Getter from my Course class

public function getShortName(){
    return $this->short_name;
}

tl;dr: Instead of compare object, compare one property of the object

You cannot change the behavior of in_array, but maybe this is helpful: php.net/manual/de/function.array-uintersect.php — colburton
– colburton, Commented May 4, 2016 at 14:27

jiboulex · Accepted Answer · 2016-05-04 14:28:40Z

1

I cannot see any existing function that would apply here. You could use array_filter to perform what you want :

function object_in_array($needle, array $array, $method) {
    $propertyToMatch = $needle->$method();
    // the $matches var will contain all the objects that have the property matching your object property
    $matches = array_filter($array, function($object) use ($propertyToMatch, $method) {
        return $propertyToMatch === $object->$method();
    });

    // If there is at least 1 result, your object property is matching one of your array of objects
    return count($matches) > 0;
}

Usage

if (object_in_array($myObject, $courses, 'getShortName')) {
    ....
}

Of course you should verify if the $method method exists and throw exceptions if not.

answered May 4, 2016 at 14:28

jiboulex

3,0412 gold badges20 silver badges31 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

theGreenCabbage Over a year ago

Thanks! What's the big O of array_filter?

jiboulex Over a year ago

sorry ? I do not understand your question

Collectives™ on Stack Overflow

Changing the way PHP in_array does object comparison

1 Answer 1

Usage

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Usage

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related