Design Patterns

JavaScript

发布订阅模式

  1. 订阅：将 callback 放入列表
  2. 发布：执行列表中所有 callback
class EventCenter {
    constructor() {
        this.events = new Map() // Map<string, Array<Function>>
    }
 
    subscribe(event, callback) {
        let list = this.events.get(event) ?? []
        list.push(callback)
        this.events.set(event, list)
    }
    
    publish(event) {
        let list = this.events.get(event) ?? []
        for (let callback of list) {
            callback()
        }
    }
}