Variable In PHP

Variable:

Variable means whose value can be changed.

Variable contains value which is stored in memory and holds some space.

In PHP, a variable starts with the $ sign, followed by the name of the variable.

2 steps to use variables

·        Variable Declaration

·        Variable Initialization

Variable Declaration:

Syntax: 

$variable_name;

Eg  1:

$x;

$x is the variable name.

Eg 2: 
$y;    
$ch;   
$name;

    Where $y,$ch and $name are the variables.

Variable Initialization:

Syntax:

$variable_name=value;

 Eg 1:

$x=89;

Where $x is the variable name and 89 is the value which assigned to $x.

 Eg 2: 

 $y=78.90;    

      $ch=’A’;    

     $name=”LearningPoint92”;

Rules for defining variables

It can have alphabets, digits and underscore.

A variable name should start with alphabet and underscore only. It can't start with digit.

No white space is allowed within variable name.

A variable name cannot be any reserved word or keyword e.g. double, float etc.

Example:

    <?php

     $name="Dipak";

     $age=78;

    $marks=12.35;

    echo "Name is: $name <br/>";  

    echo "Age is: $age <br/>";  

     echo "Marks is: $marks<br/>";  

       ?>

Output:

Name is:Dipak

Age is:78

Marks is:12.35