JavaScript计算元素的相关内容

文章 2023-07-23 来自：开发者社区

js计算数组中某个元素重复出现的个数

项目需求统计数组中每个2_0.500000_0.800000_1.000000中第一"_"前数字的个数，并生成饼图。 var alarmvalue = ["2_0.500000_0.800000_1.000000;3_0.500000_0.800000_0.757255;6_0.500000_0.800000_1.000000;8_0.500000_0.800000_0.920000", ...

文章 2018-01-30 来自：开发者社区

js计算元素距离顶部的高度及元素是否在可视区判断

前言：　　在业务当中，我们经常要计算元素的大小和元素在页面的位置信息。比如说，在一个滚动区域内，我要知道元素A是在可视区内，还是在隐藏内容区（滚动到外边看不到了）。有时还要进一步知道，元素是全部都显示在可视区，还是有部分在可视区部分在隐藏内容区。有时还要进一步知道，在隐藏内容区的那一部分是占多大的大小。so，来聊聊如何获取元素的大小和位置信息。计算元素距离顶部的高度：偏移量　　...

问答 2016-06-06 来自：开发者社区

JS计算元素的距离

如图所示•黑色框是窗口大小，也就是viewport。•红色虚线是整个页面的大小，其中一部分已经滚动超出viewport 一部分还未显示出来•红色虚线框内部的蓝绿色虚线是一个个的元素li•现在要获取某个元素到viewport顶部的距离，即红色箭头所指的那部分距离，应该如何计算。可以使用jquery

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更新时间 2024-02-12 09:29:15

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