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Using dynamic Constant and Define values ​​in PHP_PHP tutorial

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Release： 2016-07-13 10:48:09
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Constant and Define are constants in php, so below I will introduce a method to dynamically use the Constant and Define value methods. I hope it will be helpful to all students.

PHP wants to show or use dynamic Constant / Define values, how to use it? ex: The following example is a dynamic variable, but how to use dynamic Constant?

The code is as follows
 代码如下 复制代码


$a = 'abc';
$b = 'a';
echo $$b; // 印出 abc
?>
Copy code

代码如下 复制代码

define('PKEY1', 'abc');
define('PKEY2', 'def');
$i = 1;
$a = 'PKEY';
echo constant($a . $i); // abc
echo constant($a . ++$i); // def
?>

$a = 'abc'; $b = 'a'; echo $$b; // print abc ?>

PHP uses dynamic Constant / Define values ​​ You can use constant() to achieve the value of Constant, the example is as follows:
The code is as follows Copy code
define('PKEY1', 'abc'); define('PKEY2', 'def'); $i = 1; $a = 'PKEY';

echo constant($a . $i); // abc echo constant($a . ++$i); // def
?> http://www.bkjia.com/PHPjc/632795.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/632795.htmlTechArticleIn PHP, Constant and Define are constants. So below I will introduce a method to achieve dynamic use of Constant and Define value methods. , I hope it will be helpful to all students. PHP To show off or use...
Related labels：
define php and use value dynamic exist constant yes
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