Page 175 - CITS - Computer Software Application -TT

COMPUTER SOFTWARE APPLICATION - CITS

Tip: If a variable is created without a value, it is automatically assigned a value of NULL.
Variables can also be emptied by setting the value to NULL:

Change Data Type

If you assign an integer value to a variable, the type will automatically be an integer.

If you assign a string to the same variable, the type will change to a string
PHP Variables
In PHP, a variable is declared using a $ sign followed by the variable name. Here, some important points to know
about variables:
• As PHP is a loosely typed language, so we do not need to declare the data types of the variables. It automatically
analyzes the values and makes conversions to its correct datatype.
• After declaring a variable, it can be reused throughout the code.

• Assignment Operator (=) is used to assign the value to a variable.
Syntax of declaring a variable in PHP is given below:

Rules for declaring PHP variable:
• A variable must start with a dollar ($) sign, followed by the variable name.
• It can only contain alpha-numeric character and underscore (A-z, 0-9, _).
• A variable name must start with a letter or underscore (_) character.
• A PHP variable name cannot contain spaces.
• One thing to be kept in mind that the variable name cannot start with a number or special symbols.
• PHP variables are case-sensitive, so $name and $NAME both are treated as different variable.

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CITS : IT&ITES - Computer Software Application - Lesson 47 - 62