var getCurrentChapterContent = function(chapter_id,data){

$.get('data/data'+chapter_id+'.json',function(data){

if(data.result == 0){

var url = data.jsonp;

Util.getJsonp(url,function(data){

callback && callback(data);

});

}

},'json');

}这个函数的callback报错？？

这是报错内容：

index.html:185 Uncaught ReferenceError: callback is not defined

    at http://10.0.0.111:8020/H5_read/index.html:185:9

    at Object.success (http://10.0.0.111:8020/H5_read/index.html:104:8)

    at callIfDefined (http://10.0.0.111:8020/H5_read/js/jquery.jsonp.js:26:27)

    at notifySuccess (http://10.0.0.111:8020/H5_read/js/jquery.jsonp.js:173:5)

    at HTMLScriptElement.script.(anonymous function).script.(anonymous function).script.(anonymous function) (http://10.0.0.111:8020/H5_read/js/jquery.jsonp.js:245:15)