[JavaScript知识库]vue3源码

reactive

createReactiveObject

其实就是个proxy

function createReactiveObject(
  target: Target,
  isReadonly: boolean,
  baseHandlers: ProxyHandler<any>,
  collectionHandlers: ProxyHandler<any>
) {
  if (!isObject(target)) {
    if (__DEV__) {
      console.warn(`value cannot be made reactive: ${String(target)}`)
    }
    return target
  }
  // target is already a Proxy, return it.
  // exception: calling readonly() on a reactive object
  if (
    target[ReactiveFlags.RAW] &&
    !(isReadonly && target[ReactiveFlags.IS_REACTIVE])
  ) {
    return target
  }
  // target already has corresponding Proxy
  const proxyMap = isReadonly ? readonlyMap : reactiveMap
  // 如果map里面有就直接返回 提高性能
  const existingProxy = proxyMap.get(target)
  if (existingProxy) {
    return existingProxy
  }
  // only a whitelist of value types can be observed.
  const targetType = getTargetType(target)
  if (targetType === TargetType.INVALID) {
    return target
  }
  const proxy = new Proxy(
    target,
    targetType === TargetType.COLLECTION ? collectionHandlers : baseHandlers
  )
  proxyMap.set(target, proxy)
  return proxy
}

遇到看不懂的部分打个debugger看

proxy中的handler

拿到state中的name属性，进行跟踪，发生变化后会重新出发render函数


调试get函数过程

如果属性是ref对象会被接触ref

set