PHP Language Basics

Variables

PHP:   $x = 0;

PHP is a loosely typed language. No variable types in PHP. Declaring and using variables are a bit different than in other languages. In PHP, you identify and use a variable with a $ even within strings!

You assign by reference with & as in &$MyVar.

$fullname = 'Mike Prestwood';
$FullName = 'Wes Peterson';   //This is a different variable!
$Age = 38;
$Weight = 162.4;

 

echo "Your name is $fullname.
";
echo "You are $Age and weigh $Weight.
";

 PHP Variables ($x = 0;)

Some PHP Examples

Just like HTML, quotes are single or double:

<?PHP

echo "Mike's drums are over there.<br>";

echo 'Mike said, "hi!"<br>';

?>

You don't specify the variable type, the interpreter will automatically use a variant-type variable. To Declare, just assign:

<?PHP

$fullname = 'Mike Prestwood';

$FullName = 'Wes Peterson';

$Age = 38;

$Weight = 162.4;

//Variable within a literal.

echo "Your name is $fullname.<br>";

echo "You are $Age and weigh $Weight.<br>";

//$ within a literal ok too.

echo "That will be $1.52.<br>";

?>

PHP is case sensitive with variables too:

<?PHP

$fullname = 'Mike Prestwood'; //This is different...

$FullName = 'Wes Peterson';   //than this.

echo $fullname;

echo $FullName;

?>

By Reference uses "&" as in:

<?PHP
$MyOriginalVar = "Mike";
$MyNewVar = &$fullname;

echo $MyOriginalVar; //Mike
echo $MyNewVar;      //Mike

$MyNewVar = "Lisa";
echo $MyOriginalVar; //Lisa (original changed!)
echo $MyNewVar;      //Lisa
?>

More Info

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

Code:

PHP Variables ($x = 0;)