导航计时 API provides data that can be used to measure the performance of a web site. Unlike JavaScript-based libraries that have historically been used to collect similar information, the Navigation Timing API can be much more accurate and reliable.
This article currently describes Navigation Timing Level 1. There is a specification for Level 2, but it is not yet covered here.
You can use the Navigation Timing API to gather performance data on the client side, which you can then transmit to a server using
XMLHttpRequest
or other techniques.
This API lets you measure data that was previously difficult to obtain, such as the amount of time needed to unload the previous page, how long domain lookups take, the total time spent executing the window's
load
handler, and so forth.
性能
window.performance
特性返回
性能
object. While this interface is defined by the High Resolution Time API, the Navigation Timing API adds two properties:
timing
and
navigation
, of the types below.
PerformanceNavigationTiming
Provides methods and properties to store and retrieve metrics regarding the browser's document navigation events. For example, this interface can be used to determine how much time it takes to load or unload a document.
PerformanceTiming
timing
, objects of this type contain timing information that can provide insight into web page performance.
PerformanceNavigation
navigation
, which contains information explaining the context of the load operation described by this
性能
实例。
The Navigation Timing API can be used to gather performance data on the client side to be sent to a server via XHR as well as measure data that was very difficult to measure by other means such as time to unload a previous page, domain look up time,
window.onload
total time, etc.
To compute the total amount of time it took to load the page, you can use the following code:
const perfData = window.performance.timing; const pageLoadTime = perfData.loadEventEnd - perfData.navigationStart;
This subtracts the time at which navigation began (
navigationStart
) from the time at which the
load
event handler returns (
loadEventEnd
). This gives you the perceived page load time.
You can calculate the time elapsed between the beginning of a request and the completion of getting the response using code like this:
const connectTime = perfData.responseEnd - perfData.requestStart;
Here, the time at which the request was initiated (
requestStart
). from the time at which the response was finished being received (
responseEnd
).
As another example of an interesting piece of data you can obtain using the Navigation Timing API that you can't otherwise easily get, you can get the amount of time it took to render the page:
const renderTime = perfData.domComplete - perfData.domLoading;
This is obtained by starting with the time at which loading of the DOM and its dependencies is complete (
domComplete
) and subtracting from it the time at which parsing of the DOM began (
domLoading
).
| 规范 | 状态 | 注释 |
|---|---|---|
| Navigation Timing Level 2 | 工作草案 |
添加
PerformanceNavigationTiming
|
| 导航计时 | 推荐 | 初始定义。 |
Window.performance.timing
| 桌面 | 移动 | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
PerformanceTiming
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 8 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 8 | Samsung Internet Android 1.0 |
connectEnd
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
connectStart
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
domainLookupEnd
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
domainLookupStart
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
domComplete
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
domContentLoadedEventEnd
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 8 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 8 | Samsung Internet Android 1.0 |
domContentLoadedEventStart
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
domInteractive
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
domLoading
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
fetchStart
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
loadEventEnd
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
loadEventStart
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
navigationStart
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari Yes | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS Yes | Samsung Internet Android 1.0 |
redirectEnd
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
redirectStart
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
requestStart
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
responseEnd
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
responseStart
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
secureConnectionStart
弃用
|
Chrome 6 | Edge 18 | Firefox 56 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 56 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
toJSON
弃用
|
Chrome 44 | Edge 12 | Firefox 25 | IE 9 | Opera 32 | Safari Yes | WebView Android 44 | Chrome Android 44 | Firefox Android 25 | Opera Android 32 | Safari iOS Yes | Samsung Internet Android 4.0 |
unloadEventEnd
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
unloadEventStart
弃用
|
Chrome 6 | Edge 12 | Firefox 7 | IE 9 | Opera 15 | Safari 11 | WebView Android Yes | Chrome Android 18 | Firefox Android 7 | Opera Android 14 | Safari iOS 11 | Samsung Internet Android 1.0 |
完整支持
弃用。不要用于新网站。