jquery - 覆盖插件选项默认值

Question

$.fn.formreg=function(options){
 options = $.extend({}, $.fn.formreg.defaults, options);
 return this.each(function() {
 var $this =  $(this) ;  
   });         
  };


$.fn.formreg.defaults={
stepWidths:0,
 sliding_time:200,
 step_opacity:0.8,
 'step_id':'steps',
 nav_id:'navigation'
}

这就是我使用插件和传递选项值的方式。

$('#formElem').formreg({
     sliding_time:900,  //sliding time 
     step_opacity:0.2, // FieldSet alpha effect when sliding  , 1 means 100%
     step_id:'steps2', // Id of the sliding main container .. 
     nav_id:'navigation2', // Id of navigation bottom buttons..
    });

问题是无论发送什么值，值都不会改变