SRI (subresource integrity verification) has been discussed many times in the community, but as versions iterate, many conclusions need updating. This article revisits the topic based on the latest version.
Getting Started
Usage in real projects is a bit more involved:
javascript
import { useRef, useEffect, useState } from 'react'
function useIntersectionObserver(options = {}) {
const [isVisible, setIsVisible] = useState(false)
const ref = useRef(null)
useEffect(() => {
const observer = new IntersectionObserver(([entry]) => {
setIsVisible(entry.isIntersecting)
}, { threshold: 0.1, ...options })
const el = ref.current
if (el) observer.observe(el)
return () => { if (el) observer.unobserve(el) }
}, [])
return [ref, isVisible]
}
Through this approach, both the testability and scalability of the code are improved.
Source Code Analysis
Here is a complete example:
javascript
.container {
width: min(90%, 1200px);
margin-inline: auto;
padding-inline: clamp(1rem, 3vw, 3rem);
}
.grid {
display: grid;
grid-template-columns: repeat(auto-fit, minmax(min(300px, 100%), 1fr));
gap: clamp(1rem, 2vw, 2rem);
}
.card { container-type: inline-size; }
@container (min-width: 400px) {
.card__content { display: grid; grid-template-columns: 200px 1fr; }
}
Pay attention to edge case handling, which is critical in production.
Real-World Applications
The key lies in understanding the core logic:
javascript
const fs = require('fs')
const { Transform, pipeline } = require('stream')
const { promisify } = require('util')
const pipelineAsync = promisify(pipeline)
const csvToJson = new Transform({
transform(chunk, encoding, callback) {
const lines = chunk.toString().split('\n')
const headers = lines[0].split(',')
for (let i = 1; i < lines.length; i++) {
if (!lines[i].trim()) continue
const values = lines[i].split(',')
const obj = {}
headers.forEach((h, idx) => obj[h.trim()] = values[idx]?.trim())
this.push(JSON.stringify(obj) + '\n')
}
callback()
}
})
Performance optimization should be tailored to specific scenarios; not all cases require over-optimization.
Optimization Tips
We can improve it in the following ways:
javascript
import { useRef, useEffect, useState } from 'react'
function useIntersectionObserver(options = {}) {
const [isVisible, setIsVisible] = useState(false)
const ref = useRef(null)
useEffect(() => {
const observer = new IntersectionObserver(([entry]) => {
setIsVisible(entry.isIntersecting)
}, { threshold: 0.1, ...options })
const el = ref.current
if (el) observer.observe(el)
return () => { if (el) observer.unobserve(el) }
}, [])
return [ref, isVisible]
}
This approach has been running stably in production for over six months and has been practically validated.
Summary
- Understanding underlying principles is more important than memorizing APIs
- Always verify compatibility before using in production
- In team collaboration, conventions and documentation are more important than the technology itself
- Stay updated with the community; technical solutions need continuous iteration
- Don't adopt new technology just for the sake of it
