我写的 简易的事件订触发。
export const Event = function () {
// 类型
this.typeList = {}
}
Event.prototype.on = function ({type, fn}){
if (this.typeList.hasOwnProperty(type)) {
this.typeList[type].push(fn)
} else {
this.typeList[type] = []
this.typeList[type].push(fn)
}
}
Event.prototype.off = function({type, fn}) {
if (this.typeList.hasOwnProperty(type)) {
let list = this.typeList[type]
let index = list.indexOf(fn)
if (index !== -1 ) {
list.splice(index, 1)
}
} else {
console.warn('not has this type')
}
}
Event.prototype.once = function ({type, fn}) {
const fixFn = (value) => {
fn.call(this, value)
this.off({type, fn: fixFn})
}
this.on({type, fn: fixFn})
}
Event.prototype.trigger = function (type, value, context){
context = context ? context : null
if (this.typeList.hasOwnProperty(type)) {
this.typeList[type].forEach(fn => {
fn.call(context, value)
})
}
}