PHP function static variable implementation specified number of iterations

This paper mainly introduces the method that PHP uses static variable of function to realize the specified number of iterations, and analyzes the relative operation skill of PHP static variable data storage with the example form, and needs friends to refer to it.

This example describes how PHP uses a function static variable to implement a specified number of iterations. Share to everyone for your reference, as follows:

In PHP, in addition to the static member properties of a class, static variables can also be defined in a function using static. Thus, the function iteration can be completed conveniently.

Example 1:

<?phpfunction Test () {  $a = 0;  echo $a;  $a + +;}? >

In the above example, each time the test function is called, A is re-assigned a value of 0 because the variable a is re-assigned to 0 once exiting the function, because the variable a does not exist once the function exits. To complete the iteration, you need to write a count function that does not lose the count value, and define the variable $a as static:

<?phpfunction Test () {  static $a = 0;  echo $a;  $a + +;}? >

This way, $ A is only assigned at the first call and then 1 on each call and is not overridden.

This allows you to use this attribute to iterate over a specified number of times for an operation:

Example 2:(Gets the result of ejecting an array of 5 elements)

$arr = Range (1,10,1), function test ($arr) {  static $count =0;  Array_pop ($arr);  $count + +;  if ($count < 5) {    test ($arr);  } else{    var_dump ($arr); exit;}  } Test ($arr);

Operation Result:

Array (5) {[0]=> int (1) [1]=> int (2) [2]=> int (3) [3]=> int (4) [4]=> int (5)}