<div class="wrap">
    <div class="container" id="container">
        <div class="count" id="count"></div>
    </div>    
</div>

.wrap {
     width: 1366px;
      height: 900px;
}
 .container {
      width: 900px;
      height: 100%;
      margin: 0 auto;
      background-color: pink;
}
 .count {
      width: 600px;
      height: 20px;
      background-color: red;
      position: fixed;
      bottom: 0;
      left: 0;
}

(function($){ 
    $.ScrollFixed = function(el, options){ 
        var base = this; 
        base.$el = $(el); 
        base.el = el; 
        var target = base.$el; 

        // --------------       
        console.log(‘options=‘, options);
        var parentId = options.parentEl;
        var leftPos = $(parentId).offset().left + options.offsetLeft + ‘px‘;
        $(target).css(‘left‘, leftPos);
        // +++++++++++++++
        var original_left = parseInt(target.css(‘left‘)); 
        var original_right = parseInt(target.css(‘right‘)); 
       

        var _fix_position = function(){ 
            if(base.options.fixed == ‘right‘){ 
                target.css(‘right‘, ($(window).scrollLeft() + $(window).width() - $(document).width() + original_right) + ‘px‘); 
            } else if(base.options.fixed == ‘left‘){ 
                target.css(‘left‘, (original_left - $(window).scrollLeft()) + ‘px‘); 
                console.log(original_left);
            } 
        }; 

        var windowResize = function(){ 
            _fix_position(); 
        }; 

        var windowScroll = function(){ 
            _fix_position(); 
        }; 

        base.init = function(){ 
            base.options = $.extend({}, $.ScrollFixed.defaultOptions, options); 
            $(window).resize(windowResize); 
            $(window).scroll(windowScroll); 
            _fix_position(); 
            // console.log(base.options.fixed); 
        }; 

        base.init(); 
    }; 

    $.ScrollFixed.defaultOptions = { 
        fixed:‘left‘ 
    }; 

    $.fn.scrollFixed = function(options){ 
        return this.each(function(){ 
            (new $.ScrollFixed(this, options)); 
        }); 
    }; 
})(jQuery); 

$(‘#count‘).scrollFixed({fixed:‘left‘, parentEl: ‘#container‘, offsetLeft: 20});

三个参数：其中‘#count’为fixed内容，‘#container’为其祖级（或父级），该用法示例中‘20’为‘#count’相对‘#container’的left值。

fixed:‘left‘为默认项，也可以设置为fixed:‘right‘,具体操作需要根据需求作部分修改。