isset

PHP 4, PHP 5, PHP 7, PHP 8

isset - Determine if a variable is declared and is different than null

Code Examples

Example #1 isset Examples

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Example #2 isset on String Offsets

Result: bool(false) bool(true) bool(true) bool(true) bool(false) bool(false)

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Example #3

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PHP Version:

Function isset:

Manual
Code Examples

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