图片分左右不同点击效果不同的处理方法

情况是这样的，图片一分为二，鼠标在图片的左边滑动时显示向左的箭头，右边就显示右边的箭头，一分为二的条件在ie下是event.offsetX<width/2，用你写的方法，测试了下，在ff，当鼠标进入图片范围不出来的话就不会改变箭头方向，希望能有办法帮我找到问题，谢谢!

 

 

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