How can you create an array of values from an associative array $arr but only include values whose keys start with the letter 'a'?

hard📝 Application Q9 of 15

PHP - Array Functions

How can you create an array of values from an associative array $arr but only include values whose keys start with the letter 'a'?

A$values = array_values(array_filter($arr, fn($k) => str_starts_with($k, 'a')));

B$values = array_values(array_filter($arr, fn($v, $k) => str_starts_with($k, 'a'), ARRAY_FILTER_USE_BOTH));

C$values = array_keys(array_filter($arr, fn($k) => str_starts_with($k, 'a')));

D$values = array_filter($arr, fn($v) => str_starts_with($v, 'a'));

Step-by-Step Solution

Solution:

Step 1: Use array_filter with key and value
Use ARRAY_FILTER_USE_BOTH to filter by keys and values, checking keys start with 'a'.
Step 2: Extract values from filtered array
Use array_values() to get only the values from the filtered array.
Final Answer:
$values = array_values(array_filter($arr, fn($v, $k) => str_starts_with($k, 'a'), ARRAY_FILTER_USE_BOTH)); -> Option B
Quick Check:
Filter by key then get values = $values = array_values(array_filter($arr, fn($v, $k) => str_starts_with($k, 'a'), ARRAY_FILTER_USE_BOTH)); [OK]

Quick Trick: Use ARRAY_FILTER_USE_BOTH to filter by keys and values [OK]

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