unset() static variable doesn't work?

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庸人自扰
庸人自扰 2021-01-21 12:02

See this code: http://codepad.org/s8XnQJPN

function getvalues($delete = false)
{
   static $x;
   if($delete)
   {
      echo \"array before deleting:\\n\";
             


        
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  • 2021-01-21 12:33

    From the Doc

    If a static variable is unset() inside of a function, unset() destroys the variable only in the context of the rest of a function. Following calls will restore the previous value of a variable.

    function foo()
    {
        static $bar;
        $bar++;
        echo "Before unset: $bar, ";
        unset($bar);
        $bar = 23;
        echo "after unset: $bar\n";
    }
    
    foo();
    foo();
    foo();
    

    The above example will output:

    Before unset: 1, after unset: 23
    Before unset: 2, after unset: 23
    Before unset: 3, after unset: 23
    
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  • 2021-01-21 12:58

    If a static variable is unset, it destroys the variable only in the function in which it is unset. The following calls to the function (getValues()) will make use of the value before it was unset.

    This is mentioned the documentation of the unset function as well. http://php.net/manual/en/function.unset.php

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