技术问答php constant鍑芥暟鎬庝箞浣跨敤 - 扬州沐宇科技

鍦?PHP 涓紝鍙互浣跨敤 define() 鍑芥暟鏉ュ畾涔夊父閲忥紝甯搁噺涓€鏃﹁瀹氫箟鍚庯紝灏变笉鑳藉啀琚慨鏀规垨鍙栨秷瀹氫箟銆傚畾涔夊父閲忕殑涓€鑸娉曟牸寮忓涓嬶細

define("CONSTANT_NAME", "constant_value");

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define("SITE_NAME", "My Website");

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echo SITE_NAME;

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鍙﹀锛屽彲浠ヤ娇鐢?defined() 鍑芥暟鏉ユ鏌ュ父閲忔槸鍚﹀凡缁忚瀹氫箟銆備緥濡傦細

if (defined("SITE_NAME")) {
    echo "SITE_NAME 宸茬粡琚畾涔?quot;;
} else {
    echo "SITE_NAME 鏈畾涔?quot;;
}

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