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以vue组件或者插件的形式,实现throttle或者debounce

需求

  • 在业务中,会碰到许多点击请求的情况,在请求前改变一个lock变量(在lock变回来之前,点击无效),在请求回调中再改变lock.以确保在,请求回来之前,不会重复请求。或者类似的点击节流业务

实现方式

指令

 <div v-for="a in 3" :key="a" v-demo:getData="a">指令</div>
 //getData是函数名,a是传入的参数
    directives: {
    demo: {
      bind(el: Element, binding: any, vnode: VNode) {
        const that: any = vnode.context
        // console.log(binding, vnode)
        // console.log(binding.arg, binding.value)
        if (!that[binding.arg].isBind){  // 打上标记,如果已经转换了,就不转了
          that[binding.arg] = deb(that[binding.arg])
          that[binding.arg].isBind = true
        }
        el.addEventListener('click', function T(event: Event): void{
          that[binding.arg](binding.value)
        })
      },
    },
  },
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组件

  • 子组件
<template>
  <div>
    <div @click="senClick">
      <slot></slot>
    </div>
  </div>
</template>
<script lang="ts">
import Vue from 'vue';
import { Component, Prop } from 'vue-property-decorator';
@Component({})
export default class Child extends Vue {
  @Prop({ type: Number, default: 500 }) public timeOut!: number; // 时间
  @Prop({ type: String, default: 'throttle' }) public type!: string; // 类型
  @Prop() public params!: any; // 传入参数
  public message: string = 'Hello';
  public throttleLock: boolean = false;
  public debounceLock: number = 0;
  public time: any;
  public senClick(): void {
    console.log(this.timeOut, this.type, this.params);
    if (this.type === 'throttle') {
      if (this.throttleLock) {
        return;
      }
      this.throttleLock = true;
      setTimeout(() => {
        this.throttleLock = false;
      }, this.timeOut);
      this.$emit('myClick', this.params);
    } else if (this.type === 'debounce') {
      if (this.debounceLock) {
        clearTimeout(this.debounceLock);
      }
      this.debounceLock = setTimeout(() => {
        this.$emit('myClick', this.params);
      }, this.timeOut);
    } else {
      this.$emit('myClick', this.params);
    }
  }
}
</script>

<style  scoped lang='stylus'>
div {
  width: 100%;
  height: 100%;
}
</style>

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父组件

<template>
  <div class="home">
      <throttle-and-debounce @myClick="getData" :time="500" type="throttle" params="123">
        <div>我是组件内容</div>
      </throttle-and-debounce>
  </div>
</template>
import { Component, Vue } from 'vue-property-decorator';
import throttleAndDebounce from '@/components/throttleAndDebounce.vue'; 
@Component({
  components: {
    throttleAndDebounce,
  },
})
export default class home extends Vue {
public getData(e: any){
      console.log('异步数据', e)
    }
}

</script>
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plugin

  • 函数
function deb(fn: function){
  let lock: number
  return (e) => {
    if (lock){
      clearTimeout(lock)
    }
    console.log('创建闭包延迟执行')
    lock = setTimeout(() => {
      fn(e)
    }, 1500)
  }
}
export {deb}
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组件内使用

<template>
  <div class="home">
    <div @click="func(123)">function</div>
  </div>
</template>
<script lang="ts">
import { Component, Vue } from 'vue-property-decorator';
import {deb} from '@/assets'
@Component({
  components: {
    throttleAndDebounce,
  },
})
export default class home extends Vue {
     public beforeCreate(){
         this.func = deb((e: {a: number}) => {
          console.log('this', e)
        })
      }
}
</script>
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