PHP basic syntax 002 variable

Variable variables in PHP are used to store values, such as numbers, text strings, or arrays. Once a variable is set, we can reuse it in the script. All variables in PHP start with the $ symbol, and the variable names are case sensitive. The correct way to set variables in PHP is: $ var_name = value; the PHP compiler often uses the variables in PHP.

Variables are used to store values, such as numbers, text strings, or arrays.

Once a variable is set, we can reuse it in the script.

All variables in PHP start with the $ symbol, and the variable names are case sensitive.

The correct method for setting variables in PHP is:

 

$ Var_name   = Value;

PHP beginners often forget the $ symbol before the variable. In this case, the variable will be invalid.

Although variables do not need to be initialized in PHP, this is a good habit. Uninitialized variables have default values of their types-False, Zero, empty string or empty array.

<? PHP

$ VaR   =   ' PHP ' ;
$ VaR   = ' Tutorial Network ' ;
Echo " $ VaR , $ VaR " ; // Output "PHP, tutorial network"

$4 site =   ' Not yet ' ; // Illegal Change name; starting with a number
$ _ 4 site   =   ' Not yet ' ; // Valid variable name; starting with an underscore
$ I site is   =   ' Mansikka ' ; // Valid variable name; Chinese

?>

 

Variable naming rules

• The variable name must start with a letter or underscore.
• Variable names can only contain letters, numbers, and underscores.
• Variable names cannot contain spaces. If the variable name is composed of multiple words, it should be separated by underscores (for example, $ my_string) or begin with an uppercase letter (for example, $ mystring ).