property_exists()とget_object_vars()とforeach(オブジェクト)の動作の違い

オブジェクトのforeachは、get_object_vars()と反応ルールは同じ。（アクセス権のあるメンバ変数にはTRUE）。
property_exists()は、get_object_vars()より多くに反応する。（アクセス権有無無関係(PHP5.3以上)、static変数にも反応。(
メソッドは別(method_exists())））

参照：
http://php.net/manual/ja/function.property-exists.php
http://www.phppro.jp/phptips/archives/vol53/2

      1 <?php

      2 class foo {

      3     private $a;

      4     public $b = 1;

      5     public $c;

      6     private $d;

      7     static $e = 4;

      8

      9     public function test() {

     10         var_dump(get_object_vars($this));

     11     }

     12     public function obj_foreach_echo(){

     13         foreach($this as $_memberVarName => $_val){

     14             echo $_memberVarName . " => '" . $_val . "'" . PHP_EOL;

     15         }

     16     }

     17     public function obj_foreach_propertyexists($arr){

     18         foreach ($arr as $_var){

     19             print "property_exists({$_var}) :  ";

     20             var_dump(property_exists($this, $_var));

     21         }

     22     }

     23 }

     24

     25 $test = new foo;

     26 $test->B = 'dynamic';

     27 var_dump(get_object_vars($test));

     28 echo PHP_EOL;

     29 foreach($test as $_memberVarName => $_val){

     30     echo $_memberVarName . " => '" . $_val . "'" . PHP_EOL;

     31 }

     32 echo PHP_EOL;

     33 foreach(["a","b","c","d","e","f","B"] as $_var){

     34     print "property_exists({$_var}) :  ";

     35     var_dump(property_exists($test, $_var));

     36 }

     37 echo PHP_EOL;

     38 echo PHP_EOL;

     39 $test->test();

     40 echo PHP_EOL;

     41 $test->obj_foreach_echo();

     42 echo PHP_EOL;

     43 $test->obj_foreach_propertyexists(["a","b","c","d","e","f","B"]);

     44 echo PHP_EOL;

     45 echo_PHP_EOL;

     46 foreach(["a","b","c","d","e","f","B"] as $_var){

     47     print "property_exists({$_var}) :  ";

     48     var_dump(property_exists("foo", $_var));

     49 }

     50 ?>

実行結果：

[*******@tvm1560 php]$ /usr/local/php/bin/php -f foreach-object_VS_get_object_vars_VS_property_exists.php

array(3) {

  ["b"]=>

  int(1)

  ["c"]=>

  NULL

  ["B"]=>

  string(7) "dynamic"

}
b => '1'

c => ''

B => 'dynamic'
property_exists(a) :  bool(true)

property_exists(b) :  bool(true)

property_exists(c) :  bool(true)

property_exists(d) :  bool(true)

property_exists(e) :  bool(true)

property_exists(f) :  bool(false)

property_exists(B) :  bool(true)


array(5) {

  ["a"]=>

  NULL

  ["b"]=>

  int(1)

  ["c"]=>

  NULL

  ["d"]=>

  NULL

  ["B"]=>

  string(7) "dynamic"

}
a => ''

b => '1'

c => ''

d => ''

B => 'dynamic'
property_exists(a) :  bool(true)

property_exists(b) :  bool(true)

property_exists(c) :  bool(true)

property_exists(d) :  bool(true)

property_exists(e) :  bool(true)

property_exists(f) :  bool(false)

property_exists(B) :  bool(true)
property_exists(a) :  bool(true)

property_exists(b) :  bool(true)

property_exists(c) :  bool(true)

property_exists(d) :  bool(true)

property_exists(e) :  bool(true)

property_exists(f) :  bool(false)

property_exists(B) :  bool(false)

[********@tvm1560 php]$