jQuery 的$.extend和$.fn.extend作用及区别

<script type="text/javascript">$(function() {//$.alert("bxsc");$("p").alert("bxsc");//$("#bpw").Calculationnumber({//byteLength:10//});});(function($){$.extend({alert:function(msn){alert(msn+"12");}});$.fn.extend({alert:function(msn){alert(msn+"13");}});})(jQuery);$.fn.Calculationnumber = function(options){var settings = jQuery.extend({byteLength:20,attribute:$(this).attr('id')+"_tag",tyle:1},options);alert(settings.attribute);};</script>