[Typescript] Filtering properties out

List all the props with begin with "query" key in Document

type queryTypes = Extract<keyof Document, `query${string}`>
type queryyPoprDoc = {
  [Key in queryTypes]: Document[Key]
}

What if we want to filter out by value?
For example we want to get all the methods which return Element | Element[].

Idea:

  1. Construct kind of object:
{
 querySelector: "querySelector",
 alinkColor: never
 ..
}
  1. So in the object type, anything which return Element | Element[], will keep the key as string, otherwise will assign never type.

  2. Get all the string value out of the object type

type FilteredKeys<TValue, Condition> = {
  [K in keyof TValue]: TValue[K] extends Condition ? K: never
}[keyof TValue] & keyof Document
type RelevantDocumentKeys = FilteredKeys<Document, (...args: any[]) => Element | Element[]>
type ValueFilteredDoc = Pick<Document, RelevantDocumentKeys>
function load(doc: ValueFilteredDoc) {
  doc.querySelector("input")
}
posted @   Zhentiw  阅读(28)  评论(0编辑  收藏  举报
相关博文:
阅读排行:
· 阿里最新开源QwQ-32B,效果媲美deepseek-r1满血版,部署成本又又又降低了!
· Manus重磅发布:全球首款通用AI代理技术深度解析与实战指南
· 开源Multi-agent AI智能体框架aevatar.ai,欢迎大家贡献代码
· 被坑几百块钱后,我竟然真的恢复了删除的微信聊天记录!
· AI技术革命,工作效率10个最佳AI工具
历史上的今天:
2020-08-21 [Machine Learning] Multivariate Linear Regeression
2019-08-21 [Dart] Define Optional Named and Positional Parameters for Functions and Methods in Dart
2017-08-21 [D3] Animate Transitions in D3 v4
2017-08-21 [D3] Debug D3 v4 with Dev Tools
2017-08-21 [Angular] Custom directive Form validator
点击右上角即可分享
微信分享提示