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Variables are "containers" for storing information.
Creating (Declaring) PHP Variables
In PHP, a variable starts with the
<?php $txt = "Hello world!"; $x = 5; $y = 10.5; ?>
After the execution of the statements above, the variable
Note: When you assign a text value to a variable, put quotes around the value.
Note: Unlike other programming languages, PHP has no command for declaring a variable. It is created the moment you first assign a value to it.
Think of variables as containers for storing data.
A variable can have a short name (like x and y) or a more descriptive name (age, carname, total_volume).
Rules for PHP variables:
Remember that PHP variable names are case-sensitive!
The following example will show how to output text and a variable:
<?php $txt = "W3Schools.com"; echo "I love $txt!"; ?>
The following example will produce the same output as the example above:
<?php $txt = "W3Schools.com"; echo "I love " . $txt . "!"; ?>
The following example will output the sum of two variables:
<?php $x = 5; $y = 4; echo $x + $y; ?>
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PHP is a Loosely Typed Language
In the example above, notice that we did not have to tell PHP which data type the variable is.
PHP automatically associates a data type to the variable, depending on its value. Since the data types are not set in a strict sense, you can do things like adding a string to an integer without causing an error.
In PHP 7, type declarations were added. This gives an option to specify the data type expected when declaring a function, and by enabling the strict requirement, it will throw a "Fatal Error" on a type mismatch.
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