Today IT

PHP Variables

Rules for PHP variables:

• A variable starts with the $ sign, followed by the name of the variable
• A variable name must start with a letter or the underscore character
• A variable name cannot start with a number
• A variable name can only contain alpha-numeric characters and underscores (A-z, 0-9, and _ )
• Variable names are case-sensitive ($age and $AGE are two different variables)

PHP supports the following data types:

• String
• Integer
• Float (floating point numbers – also called double)
• Boolean
• Array
• Object
• NULL
• Resource

To get the data type of a variable, use the var_dump() function or use the echco gettype() function.

var_dump($name);
echo gettype($name);

Variable can assign in between double cotation.

Change Data Type- $num=(string)$age;

echo can have multiple parameters.

echo" First Name ", $fname; //echo can have multiple parameters.

echo ” First Name.$fname”; // dot sign is as concatenation
echo ” First Name $fname”;

$name=”seelan”;
$$name=”yohga”;

echo $name; //seelan
echo $seelan; //yohga
echo $$name; //yohga