How can you declare a constant variable 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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constant('echo'); // outputs 'My constant value' How do you declare a constant variable?A constant variable is one whose value cannot be updated or altered anywhere in your program. A constant variable must be initialized at its declaration. To declare a constant variable in C++, the keyword const is written before the variable's data type.
How can we declare variable in PHP?PHP Variables. A variable starts with the $ sign, followed by the name of the variable.. A variable name must start with a letter or the underscore character.. A variable name cannot start with a number.. A variable name can only contain alpha-numeric characters and underscores (A-z, 0-9, and _ ). How is a constant defined in PHP by using the keyword?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 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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