How check stdclass object is empty in php?

(PHP 4, PHP 5, PHP 7, PHP 8)

is_object — Finds whether a variable is an object

Description

is_object(mixed $value): bool

Parameters

The variable being evaluated.

Return Values

Returns true if value is an object, false otherwise.

Changelog

Examples

Example #1 is_object() example

// Declare a simple function to return an 
// array from our object
function get_students($obj)
{
    if (!is_object($obj)) {
        return false;
    }

    return

See Also

• is_bool() - Finds out whether a variable is a boolean
• is_int() - Find whether the type of a variable is integer
• is_float() - Finds whether the type of a variable is float
• is_string() - Find whether the type of a variable is string
• is_array() - Finds whether a variable is an array

mark at not4you dot com ¶

11 years ago

Unserializes data as returned by the standard PHP serialize() function. If the unserialized object is not an array, it will be converted to one, particularily useful if it returns a __PHP_Incomplete_Class.

/**
*
* @param string $data Serialized data
*
* @return array    Unserialized array
*/
function unserialize2array($data) {
    $obj = unserialize($data);
    if(is_array($obj)) return $obj;
    $arr = array();
    foreach($obj as $k=>$v) {
        $arr[$k] = $v;
    }
    unset($arr['__PHP_Incomplete_Class_Name']);
    return $arr;
}
?>

corychristison[aT-]lavacube(.dot)com ¶

17 years ago

You can use is_object($this) to detect if the function is being called via instance or procedure.

Example:

class mrClass {

    function

wadih at creationmw dot com ¶

5 years ago

Note that closures return true when passed to is_object():

echo
    is_object(
        function(){return "hello";}
    );?>

Returns true (1)

corychristison[aT-]lavacube(.dot)com ¶

17 years ago

Thank you victor AT fourstones DOT net.

I have written a function to do what victor has suggested, with the ease of use of is_object. It can be used to replace is_object(), but has an extra field [$check], to compare to a certain name. If $check is left empty, it will just check if &$object is an object.

function is_obj( &$object, $check=null, $strict=true )
{
    if( $check == null && is_object($object) )
    {
        return true;
    }
    if( is_object($object) )
    {
        $object_name = get_class($object);
        if( $strict === true )
        {
            if( $object_name == $check )
            {
                return true;
            }
        }
        else
        {
            if( strtolower($object_name) == strtolower($check) )
            {
                return true;
            }
        }
    }
}?>

This could probably be cleaned up, but it's spaced out to be easy to read.

lbjay can be emailed at reallywow dot com ¶

19 years ago

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.

will ¶

12 years ago

Just discovered:
is_a  (  object $object  ,  string $class_name  )
Which checks if the object is of this class or has this class as one of its parents

Which seems to do what a lot here are trying to replicate

victor AT fourstones DOT net ¶

17 years ago

er, I don't think that's right, especially if calling from another object instance:

function test_this()
{
    $c2 = new C2();
    $c2->func();
    $c1 = new C1();
    $c1->func();
    C1::func();
}

class C2
{
    function func()
    {
        C1::func();
    }
}

class C1
{
    function func()
    {
        if( isset($this) )
        {
            if( strtolower(get_class($this)) != 'c1' )
                print("oops\n");
            else
                print("this is ok\n" );
        }
        else
        {
            print("static call\n");
        }
    }
}

test_this();
?>

yields:
---------- run-php ----------

oops
this is ok
static call