PHP classes - Exercises, Practice, Solution

Last update on May 30 2022 11:48:05 (UTC/GMT +8 hours)

PHP classes [7 exercises with solution]

1. Write a simple PHP class which displays the following string. Go to the editor

'MyClass class has initialized !'
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2. Write a simple PHP class which displays an introductory message like "Hello All, I am Scott", where "Scott" is an argument value of the method within the class. Go to the editor
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3. Write a PHP class that calculates the factorial of an integer. Go to the editor
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4. Write a PHP class that sorts an ordered integer array with the help of sort() function.
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Sample array : array(11, -2, 4, 35, 0, 8, -9)
Output : Array ( [0] => -9 [1] => -2 [2] => 0 [3] => 4 [4] => 8 [5] => 11 [6] => 35 )
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5. Calculate the difference between two dates using PHP OOP approach. Go to the editor
Sample Dates : 1981-11-03, 2013-09-04
Expected Result : Difference : 31 years, 10 months, 1 days
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6. Write a PHP Calculator class which will accept two values as arguments, then add them, subtract them, multiply them together, or divide them on request. Go to the editor
For example :
$mycalc = new MyCalculator( 12, 6);
echo $mycalc- > add(); // Displays 18
echo $mycalc- > multiply(); // Displays 72
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7. Write a PHP script to convert a string to Date and DateTime. Go to the editor
Sample Date : '12-08-2004'
Expected Output : 2004-12-08
Note : PHP considers '/' to mean m/d/Y format and '-' to mean d-m-Y format.
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PHP Code Editor:

More to Come !

Do not submit any solution of the above exercises at here, if you want to contribute go to the appropriate exercise page.

PHP: Tips of the Day

How to Sort Multi-dimensional Array by Value?

Try a usort, If you are still on PHP 5.2 or earlier, you'll have to define a sorting function first:

Example:

function sortByOrder($a, $b) {
    return $a['order'] - $b['order'];
}

usort($myArray, 'sortByOrder');

Starting in PHP 5.3, you can use an anonymous function:

usort($myArray, function($a, $b) {
    return $a['order'] - $b['order'];
});

And finally with PHP 7 you can use the spaceship operator:

usort($myArray, function($a, $b) {
    return $a['order'] <=> $b['order'];
});

To extend this to multi-dimensional sorting, reference the second/third sorting elements if the first is zero - best explained below. You can also use this for sorting on sub-elements.

usort($myArray, function($a, $b) {
    $retval = $a['order'] <=> $b['order'];
    if ($retval == 0) {
        $retval = $a['suborder'] <=> $b['suborder'];
        if ($retval == 0) {
            $retval = $a['details']['subsuborder'] <=> $b['details']['subsuborder'];
        }
    }
    return $retval;
});

If you need to retain key associations, use uasort() - see comparison of array sorting functions in the manual

Ref : https://bit.ly/3i77vCC