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php define function usage: [define()] function defines a constant, the syntax is [define(name,value,case_insensitive)], defines a case-sensitive constant, the code is [define("GREETING ","Hello 】.
The operating environment of this tutorial: windows7 system, PHP5.6 version, DELL G3 computer. This method is suitable for all brands of computers.
Usage of php define function:
define()
The function defines a constant.
Constant is similar to a variable, except that:
After setting, the value of the constant cannot be changed
The constant name does not require a dollar sign ($) at the beginning
Scope does not affect access to constants
Constant values can only be strings or numbers
Syntax
define(name,value,case_insensitive)
Example 1
Define a case-insensitive constant:
<?php define("GREETING","Hello world!"); echo constant("GREETING"); ?>
Output:
Hello world!
Example 2
Define a case-insensitive constant :
<?php define("GREETING","Hello world!",TRUE); echo constant("greeting"); ?>
Output:
Hello world!
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