PHP json_encode 转换成空对象和空数组

对于以下对象

$foo = array( "bar1" => array(), 
  "bar2" => array() 
);

我想转换成

{ "bar1": {}, "bar2": []
}

默认情况下用json_encode($foo)得到的是

{ "bar1": [], "bar2": []
}

而加了JSON_FORCE_OBJECT参数的json_encode($foo,JSON_FORCE_OBJECT)得到的是

{ "bar1": {}, "bar2": {}
}

其实方法很简单

使用 new stdClass() 或是使用强制转换 (Object)array() 就行了.

$foo = array( "bar1" => new stdClass(), // Should be encoded as an object "bar2" => array() // Should be encoded as an array ); echo json_encode($foo);

$foo = array( "bar1" => (object)array(), // Should be encoded as an object "bar2" => array() // Should be encoded as an array ); echo json_encode($foo); // {"bar1":{}, "bar2":[]}