目前我正在学习php。我很困惑这是我的 php 代码
class OBJECT_ENUM
{
const USER = 10;
const POST = 30;
const SECURE_REQUEST = 40;
}
class OPERATION_ENUM
{
const INSERT_USER = OBJECT_ENUM::USER + 1; // <- here it gives an error
const SEND_MAIL = OBJECT_ENUM::USER + 2;
const LIKE_POST = OBJECT_ENUM::POST + 1;
const INSERT_POST = OBJECT_ENUM::POST + 2;
const ENCRYPT = OBJECT_ENUM::SECURE_REQUEST + 1;
}
error message:
Parse error: syntax error, unexpected '+', expecting ',' or ';' in /var/www/workspace/6thAssignment/include/tempCall.php on line 15
我只是不明白为什么会发生这个错误。?有人能给我解释一下吗??
提前谢谢
最佳答案
原始答案:
正如您在 http://www.php.net/manual/en/language.oop5.constants.php 中看到的那样:
The value must be a constant expression, not (for example) a variable, a property, a result of a mathematical operation, or a function call.
更新:
从 PHP 版本 5.6 now it is possible to use expressions为常数。
关于php常量数学运算,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/19510501/