Given the array $items = ['a' => 1, 'b' => 0, 'c' => 3, 'd' => null];, which foreach loop will print only keys with truthy values?
hard📝 Application Q15 of 15
PHP - Loops
Given the array $items = ['a' => 1, 'b' => 0, 'c' => 3, 'd' => null];, which foreach loop will print only keys with truthy values?
Aforeach ($items as $key => $value) { echo $key; }
Bforeach ($items as $key => $value) { if ($value === 0) echo $key; }
Cforeach ($items as $value) { if ($value) echo $value; }
Dforeach ($items as $key => $value) { if ($value) echo $key; }
Step-by-Step Solution
Solution:
Step 1: Understand truthy values in PHP
Values like 1 and 3 are truthy; 0 and null are falsy.
Step 2: Analyze each loop's condition
foreach ($items as $key => $value) { if ($value) echo $key; } prints keys only if value is truthy, matching requirement. Others print keys regardless or check wrong condition.
Final Answer:
foreach ($items as $key => $value) { if ($value) echo $key; } -> Option D
Quick Check:
Check value truthiness before echo key [OK]
Quick Trick:Use if ($value) to filter truthy values [OK]
Common Mistakes:
Printing keys without condition
Checking for zero instead of truthy
Not using key => value syntax
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