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BROWSEBYCATEGORY +Tool Basics -Language Basics Case Sensitivity Code Blocks Comments Constants◄╣ End of Statement Literals Variables +Language Details +Data Structures +Statements +Operators +Commands +Database +OOP Basics +OOP Details

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PHPLANGUAGE PHP +Tool Basics -Language Basics Case Sensitivity Code Blocks Comments Constants◄╣ End of Statement Literals Variables +Language Details +Data Structures +Statements +Operators

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PHP Language Basics

Constants

A constant is just like a variable (it holds a value) but, unlike a variable, you cannot change the value of a constant.

In PHP, you declare constants using the define keyword:

define("CONST_NAME", "Value");

Constants in PHP are case sensitive. A common standard in PHP is to use all-uppercase letters, with underscores to separate words within the name.

Syntax Example:

define('FULL_NAME', 'Mike Prestwood');
define("AGE", 25);

echo "Your name is " . FULL_NAME . ".";
echo "You are " . AGE . ".";

To/From Code Guide: Constants (Cross Ref > Language Basics) vs. Other Languages

Definition: