PHP constant Definition and Usage instance summary

What is a class constant? What we can understand in PHP is that the value is constant, so what is a class constant? In fact, the class constants are also easy to understand, we can always keep the constant value of the class is called constants, and this constant can be called the class constant. Be sure to remember that you do not need to use the "$" symbol when defining and using constants. A class constant belongs to the class itself, not to an object instance, and cannot be accessed through an object instance * cannot be decorated with public,protected,private,static * Subclasses can override constants in the parent class by calling constants in the parent class by using the (parent::)) From PHP5.3.0, a variable can be used to dynamically invoke a class. However, the value of the variable cannot be a keyword (such as self,parent or static). The definition class constants for class constants are defined using the CONST keyword: the const constant NAME = constant Value example defines and uses a class constant <?phpheader ("cont

1. PHP class constants definitions and examples

Summary: What is a class constant? What we can understand in PHP is that the amount of constant value is called constants, yes, what are class constants? In fact, the class constants are also easy to understand, we can always keep the constant value of the class is called constants, and this constant can be called the class constant. Be sure to remember that you do not need to use the "$" symbol when defining and using constants.

2. JAVASCRIPT constant Definition Detailed

Introduction: I believe that the students see this title when the face of a confused force, what? JS can constant definition? Don't tease me, okay? To be exact, JS does not have a constant (ES6 as if there is a constant definition of the keyword), but in depth we can find JS a lot of unknown nature, good use of these properties, you will find a different JS world. First of all, in JS, the object's properties actually contain its own implicit nature, such as the following object: var obj = {}; OBJ.A = 1; OBJ.B = 2; Here we define an object, obj, and define this pair:

3. Problems with the PHP constants definition

Introduction: {code ...} The constant FRUIT here can be defined as [' Apple ', ' Orage '] (this is an array bar), FRUIT should not be a number or a string? Ask for answers!!

4. PHP self-taught no00013 constants define whether a value is defined

Introduction::P HP Self-study no00013 constants define whether the value determination is defined: <?phperror_reporting (e_all ^ e_notice); Ignore error define ("Zhaowanshi", "MyName my

5. APC constant definition and PHP define comparison _php Tutorial

Summary: APC constant definitions are compared to PHP define. Recently in the cloud Platform for the initial code architecture, encountered a constant definition speed comparison problem, so do a comparison. The APC extension for PHP is described in the following paragraph in the PHP manual: H

6. PHP define constant definition and variable difference _php tutorial

Summary: PHP define constant definitions differ from variables. Constants must be defined before they are used, or the program execution will fail. Use the Define () function in the PHP tutorial to define constants. 1, Syntax format: Define (constant name, constant value); For example:

7. PHP Basics-Constants-variable-related basic functions _php tutorial

Summary: Basic PHP-Constants-variable-related underlying functions. PHP Basics-Constants-variable-related underlying function comment statements//single-line # single-line/* Multiline Comment *//** * Document Comment */constant definition Custom constant constant name case-sensitive system

8. Front-end learning PHP constants, learn PHP constants _php Tutorial

Introduction: The Front-end learning PHP constants, learn PHP constants. Front-end learning PHP constants, Learning PHP Constants directory [1] constant definition [2] Custom constants [3] System constants [4] constant values [5]defined () constants define constants like variables, but constants once determined

9. The difference between const and define in the definition of PHP constants

Summary: The difference between const and define in the definition of PHP constants in the constant definition in PHP, can be used to const and define the two methods of defining constants, then what is their difference? Here are 8 ways to analyze the difference between const and define in a PHP constant definition: 1, the definition of const for a class member constant, once defined, cannot be modified. Define is not available for definitions of class member constants and can be used for global constants. 2, the const can be used in the class, define cannot. 3. Const cannot define constants in conditional statements

PHP variable Constant Definition method

Description: The PHP variable constant definition method defines some common static constants such as PHP. 1. Define constant define ("CONSTANT", "Hello World"); Constants can only contain scalar data (boolean,integer,float and string). When calling a constant, simply use the name to get the value of the constant, not the "$" symbol, such as: Echo CONSTANT; note: Constants and (global) variables are in different namespaces.

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