How to use the static variables of PHP functions

This time to bring you the use of static variables PHP function, the use of PHP function static variables of the note, the following is the actual case, together to see.

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)}

Believe that you have read the case of this article you have mastered the method, more exciting please pay attention to the PHP Chinese network other related articles!

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