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How Can I Filter a PHP Array to Keep Only Elements with a Specific Value, Preserving Original Keys?
How Can I Filter a PHP Array to Keep Only Elements with a Specific Value, Preserving Original Keys?
Dec 23, 2024 pm 09:06 PM
Filtering an Array Based on a Value Condition with PHP
An array can be filtered according to a specified condition using built-in PHP functions. Consider the following scenario:
Objective:
Filter an array to retain elements where the value equals 2 and remove all others, preserving the original keys.
Original Array:
$fullArray = array('a' => 2, 'b' => 4, 'c' => 2, 'd' => 5, 'e' => 6, 'f' => 2);
Expected Result:
array('a' => 2, 'c' => 2, 'f' => 2);
Solution:
To achieve this, we can utilize the array_filter() function with a custom callback function that evaluates the value condition. Here's an example:
function filterArray($value){
return ($value == 2);
}
$filteredArray = array_filter($fullArray, 'filterArray');
foreach($filteredArray as $k => $v){
echo "$k = $v";
}
In this solution:
- The filterArray() function serves as a callback function for array_filter(), testing each element's value against the condition (returns true for equality to 2).
- The array_filter() function applies the callback to each element and returns a new array containing only the elements that pass the condition.
- The resulting $filteredArray contains the desired elements with the original keys preserved.
- Finally, a loop iterates over the filtered array to display the filtered elements.
This solution provides a straightforward and efficient way to filter an array based on a specific value condition, retaining the original keys, thus meeting the desired outcome.
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