基于jQuery实现一个marquee无缝滚动的插件

/**

 * 类库名称：jQuery.marquee

 * 实现功能：基于 jquery 实现的 marquee 无缝滚动插件

 * 作者主页：http://www.miaoqiyuan.cn/

 * 联系邮箱：mqycn@126.com

 * 使用说明：http://www.miaoqiyuan.cn/p/jquery-marquee

 * 最新版本：http://git.oschina.net/mqycn/jQueryMarquee

*/

jQuery.fn.extend({

  marquee :function(opt, callback){

    opt = opt || {};

    opt.speed = opt.speed || 30;

    opt.direction = opt.direction ||'left';

    opt.pixels = opt.pixels || 2;

    switch( opt.direction ){

      case"left":

      case"right":

        opt.weight ="width";

        opt.margin ="margin-left";

        opt.tpl ='

        break;

      case"top":

      case"bottom":

        opt.weight ="height";

        opt.margin ="margin-top";

        opt.tpl   ='

        break;

      default:

        throwError("[jQuery.marquee.js] Options.direction Error!");

    }

    switch( opt.direction ){

      case"left":

      case"top":

        opt.addon = -1;

        break;

      case"right":

      case"bottom":

        opt.addon = 1;

        break;

      default:

        throwError("[jQuery.marquee.js] Options.direction Error!");

    }

    callback =typeofcallback =="function"? callback :function(){};

    //设置宽度

    $(this).each(function(){

      if(this.control ){

        clearInterval(this.control);

      }else{

        //如果第一次执行，初始化代码

        $(this)

          .data(opt.weight, opt.weight =='width'? $(this).find("table").width() : $(this).find("table").height())

          .width($(this).data(opt.weight) * 2)

          .html(opt.tpl.replace(/\[TABLE\]/ig, $(this).html()))

          .mouseover(function(){

            $(this).data("pause",true);

          }).mouseout(function(){

            $(this).data("pause",false);

          });

      }

      this.control = setInterval((function(){

        if( $(this).data("pause") ){

          return;

        }

        var_margin = parseInt($(this).css(opt.margin)) + opt.addon * opt.pixels;

        if( opt.addon == -1 && _margin + $(this).data(opt.weight) < 0 ){

          _margin = 0;

        }elseif( opt.addon == 1, _margin > 0 ){

          console.log(_margin < 0,$(this).data(opt.weight));

          _margin = -1 * $(this).data(opt.weight);

        }

        $(this).css(opt.margin, _margin +"px");

        callback.bind(this)();

      }).bind(this), opt.speed);

    });

    return$(this);

  }

});

/**

 * IE8插件（解决 function 不支持 bind 的问题），非原创

*/

if(!Function.prototype.bind) {

  Function.prototype.bind =function(oThis) {

    if(typeofthis!=="function") {

      thrownewTypeError("[jQuery.marquee.ie8] Caller is not a function");

    }

    varaArgs = Array.prototype.slice.call(arguments, 1),

      fToBind =this,

      fNOP =function() {},

      fBound =function() {

        returnfToBind.apply(thisinstanceoffNOP  && oThis ?this: oThis,  aArgs.concat(Array.prototype.slice.call(arguments)));

      };

    fNOP.prototype =this.prototype;

    fBound.prototype =newfNOP();

    returnfBound;

  };

}

$("scroll-a").marquee();

$("scroll-b").marquee({direction:'top'});

$("scroll-c").marquee({direction:'top',pixels:2,speed:30});

$("scroll-d").marquee({direction:"top",pixels:2,speed:30},function(){

  console.log("执行了一次");

});