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
The constant used to learn php at the front end and the constant used to learn php* Directory [1] definition constant [2] constant detection [3] system constant [4] before magic constant
Constants do not exist in javascript. in php, they are
The definition of APC constant is compared with define of PHP. Recently, when I was working on the preliminary code architecture of the cloud platform, I encountered a constant definition speed comparison problem, so I would like to make a
in our previous article, we introduced the use of PHP define examples, I believe that we have a certain understanding of define, today we introduce you to the PHP constant define and the difference between const detailed!
A constant is a simple
A constant can be interpreted as a constant volume. After a constant is defined, it cannot be changed anywhere in the script. A constant consists of letters, underscores, and mathematics. However, a number cannot appear as the first letter. Use the
Constants are a very new data type in php. I will introduce some usage of PHP constants in detail for beginners. if you need to know them, refer to the PHP constant define () function.
Constants are a very new data type in php. I will introduce some
1. Custom Constants
* Must be defined with function define ()* The value can not be changed after the definition is finished* Use the constant name directly, not as a variable in front plus $sFor example: Define ("PI", 3.14); Define a constant$area
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
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: Define ("php360",
PHP constantsThe define () function is used to define constants. Once a constant is defined, it cannot be changed or undefined.Example of defining constants: The code is as follows:Copy code Define ("CONSTANT", "Hello! ");Echo CONSTANT;?>
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