The $ operator in PHP is used to declare a variable. In PHP, a variable starts with the $ sign followed by the name of the variable. For example, below is a string variable:
$var_name = "Hello World!";
The $var_name is a normal variable used to store a value. It can store any value like integer, float, char, string etc. On the other hand, the $$var_name is known as reference variable where $var_name is a normal variable. The $$var_name used to refer to the variable with the name as value of the variable $var_name.
Examples:
Input : $Hello = "Geeks for Geeks"
$var = "Hello"
echo $var
echo $$var
Output : Hello
Geeks for Geeks
Input : $GFG = "Welcome to neveropen"
$var = "GFG"
echo $var
echo $$var
Output : GFG
Welcome to neveropen
Explanation: In the above example, $var stores the value “Hello”, so $$var will refer to the variable with name Hello i.e., $Hello.
Below program will illustrate the $ and $$ operator in PHP.
<?php // Variable declaration and initialization $var = "Hello"; $Hello = "neveropen"; // Display the value of $var and $$var echo $var . "\n"; echo $$var; echo "\n\n"; // Variable declaration and initialization $var = "GFG"; $GFG = "Welcome to neveropen"; // Display the value of $var and $$var echo $var. "\n"; echo $$var; ?> |
Output:
Hello neveropen GFG Welcome to neveropen
