PHP: String Syntax

Apostrophe Delimiter

Use APOSTROPHE delimiter for literal string.

<?php
# APOSTROPHE quoted string's content is literal.
# The \n is printed as blackslash and n
echo 'hi there\n something';
?>

QUOTATION MARK Delimiter

Use QUOTATION MARK delimiter for interpreted string.

When using QUOTATION MARK, any variables in the following forms are evaluated and its value used.

• $variableName
• {$variableName}
• ${variableName} → deprecated.

<?php
$x = 4;
# double quoted strings are interpreted. \n is a new line. Variable become values
echo "I have $x apples";
// I have 4 apples
?>

<?php
// string can contain Unicode characters, or literal line break
echo "α β
and ♥";
?>

<?php
$x = 3;
$y = 4;
echo "i have {$x} cats {$y} dogs";
# i have 3 cats 4 dogs
?>

Escape Sequence

the following characters has special meaning.

• \n → new line
• \r → carriage return
• \t → tab

• ASCII Characters