unregisterFilter() - 注销过滤器
void unregisterFilter(string type,
string|array callback);注销过滤器。 参数如下：
type defines the type of the filter. Valid values are "pre", "post", "output" and "variable".
callback defines the PHP callback. it can be either:
A string containing the function name
An array of the form array(&$object, $method) with
&$object being a reference to an
object and $method being a string
containing the method-name
An array of the form
array($class, $method) with
$class being the class name and
$method being a method of the class.
参见
registerFilter().