PHP static statics Variable detailed

PHP static statically variable

Another important feature of variable scope is static variable. A static variable exists only in a local function field, but its value is not lost when the program executes out of this scope. Take a look at the following example:

Examples demonstrating the need for static variables

 
  
  

  
   
   
? Php
  
   
   
function Test ()
  
   
   
{
  
   
   
$w 3sky = 0;
  
   
   
echo $w 3sky;
  
   
   
$w 3sky++;
  
   
   
}
  
   
   
?>
 
  
  

This function is not useful because the value of $w 3sky is set to 0 and output "0" each time it is invoked. Adding a variable to the $w 3sky++ does not work, because once the function is exited, the variable $w 3sky does not exist. To write a count function that does not lose the value of this count, define the variable $w 3sky as static:

Examples of using static variables

 
  
  

  
   
   
? Php
  
   
   
function Test ()
  
   
   
{
  
   
   
static $w 3sky = 0;
  
   
   
echo $w 3sky;
  
   
   
$w 3sky++;
  
   
   
}
  
   
   
?>
 
  
  

Now, each call to the Test () function will output $w 3sky value and add one.