超越PHP - Exceed PHP: is_object

描述

bool is_object ( mixed var)

如果 var 是一个 object 则返回 TRUE，否则返回 FALSE。

参见 is_bool()、is_int()、is_integer()、is_float()、is_string() 和 is_array()。

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is_object

lbjay can be emailed at reallywow dot com
03-May-2003 03:18

I'm not even sure how to articulate this, so I'm going to just include test
code. Maybe someone else will someday wonder the same
thing.

<?
    error_reporting(E_ALL);
    class
testParent
    {
        var $child;

        function
testParent()
        {
            $this->child = new
testChild();
        }
    }

    class testChild
    {
 
      function testChild()
        {
        }
    }

   
$parent = new testParent();
    $parent2 = 'foobar';

    print
join(',', Array(
        is_object($parent) ? 'yes' : 'no',
       
is_object($parent->child) ? 'yes' : 'no',
        is_object($parent2)
? 'yes' : 'no',
        is_object($parent2->child) ? 'yes' : 'no'

   ));

?>

This prints "yes,yes,no,no". Basically
this shows that you can use is_object to test if the child object is an
object without worrying about an error if the parent object isn't an object
either.

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