在此页

• 句法
• 范例
• 规范
• 浏览器兼容性
• 相关话题

这是 实验性技术
检查 浏览器兼容性表格 要小心谨慎在生产中使用这之前。

IntersectionObserverEntry interface's read-only intersectionRatio property tells you how much of the target element is currently visible within the root's intersection ratio, as a value between 0.0 and 1.0.

句法

var intersectionRatio = IntersectionObserverEntry.intersectionRatio;
					

值

A number between 0.0 and 1.0 which indicates how much of the target element is actually visible within the root's intersection rectangle. More precisely, this value is the ratio of the area of the intersection rectangle ( intersectionRect ) to the area of the target's bounds rectangle ( boundingClientRect ).

If the area of the target's bounds rectangle is zero, the returned value is 1 if isIntersecting is true or 0 if not.

范例

In this simple example, an intersection callback sets each target element's opacity to the intersection ratio of that element with the root.

function intersectionCallback(entries) {
  entries.forEach(function(entry) {
    entry.target.style.opacity = entry.intersectionRatio;
  });
}
					

To see a more concrete example, take a look at Handling intersection changes in Timing element visibility with the Intersection Observer API .

规范

规范	状态	注释
Intersection Observer The definition of 'IntersectionObserverEntry.intersectionratio' in that specification.	工作草案	初始定义

浏览器兼容性

The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
intersectionRatio	Chrome 51	Edge 15	Firefox 55 55 不支持 53 — 55 Disabled Disabled ). To change preferences in Firefox, visit	IE No	Opera Yes	Safari ?	WebView Android 51	Chrome Android 51	Firefox Android ?	Opera Android ?	Safari iOS ?	Samsung Internet Android 5.0

图例

完整支持

完整支持

不支持

不支持

兼容性未知 ?

兼容性未知

实验。期望将来行为有所改变。

实验。期望将来行为有所改变。

用户必须明确启用此特征。

用户必须明确启用此特征。

元数据

• 最后修改： 2019 年 3 月 23 日

相关话题

1. 交集观测器 API
2. IntersectionObserverEntry
3. 特性

   1. boundingClientRect
   2. intersectionRatio
   3. intersectionRect
   4. isIntersecting
   5. rootBounds
   6. target
   7. time
4. Related pages for Intersection Observer API

   1. IntersectionObserver