1121项目第四天

Posted on 2016-11-21 22:10  王小明爱红领巾  阅读(79)  评论(0)  编辑  收藏  举报 
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这是运用滚动监听实现的图片渐显渐隐的效果，滚轮滚动到下方图片显示，滚动回去图片隐藏，运用了函数