一个用户请求期间php中的静态变量

Question

I try to use a variable in each instance for a class.

My example class:

class test {
    private static $gvalue;

    function setValue($value)
    {
        $this->gvalue = $value;
    }

    function getValue()
    {
        return $this->gvalue;
    }

}

Now I create to instances of this class "test" and print out some values.

$obj = new test();
$obj2 = new test();
echo "1: ";
echo $obj->getValue();
echo " / ";
echo $obj2->getValue();
$obj->setValue("green");
echo "<BR>2: ";
echo $obj->getValue();
echo "/";
echo $obj2->getValue();

My expectation was to get the following output:

1: / 2: green/green

But the result is:

1: / 2: green/

Did I understand something wrong? Or ist that not possible in PHP? Goal at the end. I would like to set some variables/arrays during the creation of an instance (__construc) and us that for every instance during the code (per user request).

Answer 1

You have to change how you access the static property in your method implementation:

<?php

class Test {
  private static $gvalue;

  function setValue($value) {
    self::$gvalue = $value;
  }

  function getValue() {
    return self::$gvalue;
  }
}

$obj1 = new Test();
$obj2 = new Test();
echo sprintf("1: %s/%s
", $obj1->getValue(), $obj2->getValue());

$obj1->setValue("green");
echo sprintf("2: %s/%s
", $obj1->getValue(), $obj2->getValue());

The output of that is:

1: /
2: green/green