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<?php $requiredFields = ['name', 'age', 'hair_colour']; // Note: $errorString is not initialised foreach ( $requiredFields as $field ) { if ( ! isset($_POST[$field]) ) { $errorString .= "Missing required field '$field'. "; } } echo $errorString;
Output for 8.0.1 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
Warning: Undefined variable $errorString in /in/pP5CU on line 8 Missing required field 'name'. Missing required field 'age'. Missing required field 'hair_colour'.
Output for 7.4.0 - 7.4.33
Notice: Undefined variable: errorString in /in/pP5CU on line 8 Missing required field 'name'. Missing required field 'age'. Missing required field 'hair_colour'.
preferences:
123.82 ms | 407 KiB | 5 Q