主题
分析
¥Analytics
Next.js 内置了对测量和报告性能指标的支持。你可以使用 useReportWebVitals
钩子自行管理报告,或者 Vercel 提供 托管服务 来自动为你收集和可视化指标。
¥Next.js has built-in support for measuring and reporting performance metrics. You can either use the useReportWebVitals
hook to manage reporting yourself, or alternatively, Vercel provides a managed service to automatically collect and visualize metrics for you.
客户端检测
¥Client Instrumentation
对于更高级的分析和监控需求,Next.js 提供了一个 instrumentation-client.js|ts
文件,它会在应用的前端代码开始执行之前运行。这非常适合设置全局分析、错误跟踪或性能监控工具。
¥For more advanced analytics and monitoring needs, Next.js provides a instrumentation-client.js|ts
file that runs before your application's frontend code starts executing. This is ideal for setting up global analytics, error tracking, or performance monitoring tools.
要使用它,请在应用的根目录中创建一个 instrumentation-client.js
或 instrumentation-client.ts
文件:
¥To use it, create an instrumentation-client.js
or instrumentation-client.ts
file in your application's root directory:
js
// Initialize analytics before the app starts
console.log('Analytics initialized')
// Set up global error tracking
window.addEventListener('error', (event) => {
// Send to your error tracking service
reportError(event.error)
})
构建你自己的
¥Build Your Own
jsx
'use client'
import { useReportWebVitals } from 'next/web-vitals'
export function WebVitals() {
useReportWebVitals((metric) => {
console.log(metric)
})
}
jsx
import { WebVitals } from './_components/web-vitals'
export default function Layout({ children }) {
return (
<html>
<body>
<WebVitals />
{children}
</body>
</html>
)
}
由于
useReportWebVitals
钩子需要"use client"
指令,因此性能最佳的方法是创建根布局导入的单独组件。这将客户端边界专门限制为WebVitals
组件。¥Since the
useReportWebVitals
hook requires the"use client"
directive, the most performant approach is to create a separate component that the root layout imports. This confines the client boundary exclusively to theWebVitals
component.
查看 API 参考 了解更多信息。
¥View the API Reference for more information.
网络生命体
¥Web Vitals
网络生命体 是一组有用的指标,旨在捕捉网页的用户体验。以下 Web Vitals 均包含在内:
¥Web Vitals are a set of useful metrics that aim to capture the user experience of a web page. The following web vitals are all included:
到第一个字节的时间(TTFB)
¥Time to First Byte (TTFB)
第一次内容丰富的绘画(FCP)
¥First Contentful Paint (FCP)
最大的内容涂料(LCP)
¥Largest Contentful Paint (LCP)
第一个输入延迟(最终检测结果)
¥First Input Delay (FID)
累积布局偏移(CLS)
¥Cumulative Layout Shift (CLS)
与 Next 绘画的交互(INP)
¥Interaction to Next Paint (INP)
你可以使用 name
属性处理这些指标的所有结果。
¥You can handle all the results of these metrics using the name
property.
tsx
'use client'
import { useReportWebVitals } from 'next/web-vitals'
export function WebVitals() {
useReportWebVitals((metric) => {
switch (metric.name) {
case 'FCP': {
// handle FCP results
}
case 'LCP': {
// handle LCP results
}
// ...
}
})
}
jsx
'use client'
import { useReportWebVitals } from 'next/web-vitals'
export function WebVitals() {
useReportWebVitals((metric) => {
switch (metric.name) {
case 'FCP': {
// handle FCP results
}
case 'LCP': {
// handle LCP results
}
// ...
}
})
}
将结果发送到外部系统
¥Sending results to external systems
你可以将结果发送到任何端点,以测量和跟踪站点上的真实用户性能。例如:
¥You can send results to any endpoint to measure and track real user performance on your site. For example:
js
useReportWebVitals((metric) => {
const body = JSON.stringify(metric)
const url = 'https://example.com/analytics'
// Use `navigator.sendBeacon()` if available, falling back to `fetch()`.
if (navigator.sendBeacon) {
navigator.sendBeacon(url, body)
} else {
fetch(url, { body, method: 'POST', keepalive: true })
}
})
需要了解:如果你使用 谷歌分析,则使用
id
值可以让你手动构建度量分布(以计算百分位数等)¥Good to know: If you use Google Analytics, using the
id
value can allow you to construct metric distributions manually (to calculate percentiles, etc.)
js
> useReportWebVitals((metric) => {
> // Use `window.gtag` if you initialized Google Analytics as this example:
> // https://github.com/vercel/next.js/blob/canary/examples/with-google-analytics
> window.gtag('event', metric.name, {
> value: Math.round(
> metric.name === 'CLS' ? metric.value * 1000 : metric.value
> ), // values must be integers
> event_label: metric.id, // id unique to current page load
> non_interaction: true, // avoids affecting bounce rate.
> })
> })
> ```
> 阅读有关 [将结果发送至 Google Analytics](https://github.com/GoogleChrome/web-vitals#send-the-results-to-google-analytics) 的更多信息。
>
> ¥Read more about [sending results to Google Analytics](https://github.com/GoogleChrome/web-vitals#send-the-results-to-google-analytics).