How Can I Accurately Echo Boolean Values (true/false) in PHP?

PHP Echo Boolean Values Accurately

In PHP, casting a boolean value to a string typically results in "1" or an empty string depending on its truthiness. However, some cases may require explicitly printing "false" when the boolean value is indeed false.

Consider the following code:

$bool_val = (bool)false;
echo $bool_val;

This code will not output anything, as casting false to a string results in an empty string. Similarly, for true, casting to a string results in "1".

Alternative Solutions

To explicitly echo "false" or "0" when the boolean value is false, the following options can be used:

• Ternary Operator:

echo $bool_val ? 'true' : 'false';

This ternary operator evaluates the value of $bool_val and returns "true" if it's true, or "false" if it's false.

• Coalesce Operator:

echo $bool_val ?? 'false';

The Coalesce Operator, introduced in PHP 7.0, returns the first non-null value of its arguments. In this case, if $bool_val is false (which evaluates to null), the "false" string will be returned.

• Logical Not and Conditional Operator:

echo !$bool_val ? 'false' : '';

This technique uses the logical "not" operator to reverse the boolean value. If $bool_val is false, it will be reversed to true, causing the conditional operator to evaluate to "false".

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