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<?php function isJson($string) { $decoded = json_decode($string); return (json_last_error() == JSON_ERROR_NONE); } if ( isJson("hello") ) { echo "valid JSON"; } else { echo "not valid JSON"; }
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 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
not valid JSON
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124.23 ms | 407 KiB | 5 Q