PHP Static Variables

Scope can be defined as the range of availability a variable has to the program in which it is declared. PHP variables can be one of four scope types:

• Local variables
• Function parameters
• Global variables
• Static variables.

Static Variables:

The final type of variable scoping that I discuss is known as static. In contrast to the variables declared as function parameters, which are destroyed on the function's exit, a static variable will not lose its value when the function exits and will still hold that value should the function be called again.

You can declare a variable to be static simply by placing the keyword STATIC in front of the variable name.

<? function keep_track() { STATIC $count = 0; $count++; print $count; print " "; } keep_track(); keep_track(); keep_track(); ?>

This will produce following result.

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