How is a constant defined in php?
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A constant is an identifier (name) for a simple value. As the name suggests, that value cannot change during the execution of the script (except for magic constants, which aren't actually constants). Constants are case-sensitive. By convention, constant identifiers are always uppercase. Show
The name of a constant follows the same rules as any label in PHP. A valid constant name starts with a letter or underscore, followed by any number of letters, numbers, or underscores. As a regular expression, it would be expressed thusly: It is possible to define() constants with reserved or even invalid names, whose value can only be retrieved with the constant() function. However, doing so is not recommended. Example #1 Valid and invalid constant names
Like superglobals, the scope of a constant is global. Constants can be accessed from anywhere in a script without regard to scope. For more information on scope, read the manual section on variable scope.
wbcarts at juno dot com ¶ 10 years ago
('MIN_VALUE', '0.0'); // RIGHT - Works OUTSIDE of a class definition.
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MAX_VALUE = 10; Sumon Mahmud (Abu Taleb) ¶ 2 years ago
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DEBUG) {
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define('BOOK',100); php at webflips dot net ¶ 8 years ago
constant('echo'); // outputs 'My constant value' How do you define constant explain using define () function in PHP?Constants can be defined using the const keyword, or by using the define()-function. While define() allows a constant to be defined to an arbitrary expression, the const keyword has restrictions as outlined in the next paragraph. Once a constant is defined, it can never be changed or undefined.
How constant can be defined?A constant is a value that cannot be altered by the program during normal execution, i.e., the value is constant. When associated with an identifier, a constant is said to be “named,” although the terms “constant” and “named constant” are often used interchangeably.
How can you declare variable and constant in PHP?Constant vs Variables
A constant can only be defined using define() function. It cannot be defined by any simple assignment. A variable can be defined by simple assignment (=) operator. There is no need to use the dollar ($) sign before constant during the assignment.
How do you declare an array constant in PHP?Array constants can now be defined using the define() function. In PHP 5.6, they could only be defined using const keyword.
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