I hear it"s a sibling comparison, but how to implement
by code, such as
Old js object
{"div","class=a", {children}}
New js object
{" div","class=b", {children}}
comparison between js object and js object
1. I want to know what method (code) is used at the bottom to compare
is it traversal?
2. Did you find the child nodes behind the differences and no longer compare them? Directly delete and then regenerate?
class VNode {
constructor (tagName, props, children) {
this.tagName = tagName
this.props = props
this.children = children
}
render () {
const { props, children } = this,
dom = document.createElement(this.tagName)
Object.entries(props).map(([key, value]) => dom.setAttribute(key, value))
children.map(o => dom.appendChild(o instanceof VNode ? o.render() : document.createTextNode(o)))
return dom
}
}
const h = (tagName, props, children) => new VNode(tagName, props, children)learn about the createClass of react
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