• Aikins Laryea
• PHP,Web Development

Variables and types

Variables

As we already know, variables are containers that can store information, or values to be precise.

<?php
$name = "Slim Shady";
?>

There! Now the $name variable stores the value "Slim Shady".

Strings

"Slim Shady" is a so-called string, a sequence of characters wrapped in single or double quotes.

<?php
 $first = 'Slim ';
 $second = "Shady";
 echo $first, $second;
?>

//Output Below

Slim Shady

See that? It doesn't matter if we use single or double quotes, as long as we want them to be part of the string.

Combining strings

We can do lots of fun things with strings. For example, we can add them together.

<?php
 $intro = "Hi, my name is ";
 $name = "Slim Shady";
 echo $intro . $name;
?> 

//Output Below

Hi, my name is Slim Shady

Well said! The . sign is a so-called operator that combines the values of two or more strings.

Integers

Let's talk numbers. An integer is another data type that can represent whole numbers.

<?php
 $number = 720;
 echo $number;
?>

//Output Below

720

That's right! We've stored an integer, which can be positive or negative, in $number.

Floats

A float, or floating-point number, is a data type for numbers with a decimal point.

<?php 
 $number = 5.28;
 echo $number;
?>

//Output Below

5.28

Bingo! We've stored a float in $number. Just like integers, these values can be positive or negative.

Operators

We can use operators to do math with numbers.

Let's try and add these numbers.

<?php
 $number1 = 49;
 $number2 = 7;
 echo $number1 + $number2;
?> 

//Output Below

56

See that? The + sign adds the numbers together just like a regular calculator.

Psst: The -, *, and \ signs also work exactly as you'd expect them to.

Shortcuts

If we want to in increase the value of a variable by, say, 10, we can use a shortcut.

<?php
 $number = 16;
 echo $number += 10;
?>

//Output Below

26

Perfect! +=, -=, *=, and /= give the result of the operation back to the variable.

Booleans

A boolean is a data type that can only be true or false.

Which of these might be the correct way to assign a boolean value?

<?php
 $boolean = true;
 echo $boolean;
?>

//Output Below

1

See that? When we use echo with a true boolean, 1 is printed. If the boolean were false, 0 would be printed.

Constants

Finally, constants are almost like variables, except that their values are, well, constant.

<?php
 define("PI", 3.1415926535898);
 echo PI;
?>

//Output Below

3.1415926535898

Yes! We don't need the $ sign with constants and usually write their names in uppercase letters.

Laryea

Web Developer