You have an array $words = ['one', '', 'three', null, 'five'];. You want to join only the non-empty, non-null elements with a comma. Which code correctly does this?

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PHP - String Functions

You have an array $words = ['one', '', 'three', null, 'five'];. You want to join only the non-empty, non-null elements with a comma. Which code correctly does this?

A$filtered = array_filter($words); echo implode(', ', $filtered);

Becho implode(', ', $words);

C$filtered = array_map(trim, $words); echo implode(', ', $filtered);

D$filtered = array_filter($words, fn($w) => $w !== ''); echo implode(', ', $filtered);

Step-by-Step Solution

Solution:

Step 1: Remove empty and null elements using array_filter
array_filter without callback removes falsy values like empty string and null.
Step 2: Use implode to join filtered array with comma
Joining filtered elements with ', ' produces the desired string.
Final Answer:
$filtered = array_filter($words); echo implode(', ', $filtered); -> Option A
Quick Check:
array_filter removes empty/null, then implode joins [OK]

Quick Trick: Filter falsy values before implode to exclude empties [OK]

Common Mistakes:

Using implode directly without filtering
Using array_map(trim) which doesn't remove null
Filtering only empty strings but not null

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You have an array $words = ['one', '', 'three', null, 'five'];. You want to join only the non-empty, non-null elements with a comma. Which code correctly does this?

Step 1: Remove empty and null elements using array_filter

Step 2: Use implode to join filtered array with comma

Final Answer:

Quick Check:

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