ts防抖节流

防抖动和节流本质是不一样的。防抖动是将多次执行变为最后一次执行，节流是将多次执行变成每隔一段时间执行。

/**
 * @des 防抖 ，多次只执行最后一次
 * @param func 需要包装的函数
 * @param delay 延迟时间，单位ms
 * @param immediate 是否默认执行一次(第一次不延迟)
 */
class Debounced {
  public use = (
    func: Function,
    delay: number,
    immediate: boolean = false
  ): Function => {
    let timer: NodeJS.Timeout;
    return (...args: any) => {
      if (immediate) {
        func.apply(this, args);
        immediate = false;
        return;
      }
      clearTimeout(timer);
      timer = setTimeout(() => {
        func.apply(this, args);
      }, delay);
    };
  };
}

/**
 * @des 节流，多次都会执行，只是间隔一段时间再执行
 * @param func 需要包装的函数
 * @param delay 延迟时间，单位ms
 * @param immediate 是否默认执行一次(第一次不延迟)
 */
class Throttle {
  private timer: NodeJS.Timeout | undefined;
  private stop: boolean = false;
  private death: boolean = false;
  public use(
    func: Function,
    delay: number,
    immediate: boolean = false
  ): Function {
    let flag = true;
    const self = this;
    return (...args: any) => {
      if (this.death) {
        func.apply(this, args);
        return;
      }
      if (this.stop) {
        func.apply(this, args);
        return;
      }
      if (immediate) {
        func.apply(this, args);
        immediate = false;
        return;
      }
      if (!flag) {
        return;
      }
      flag = false;
      self.timer = setTimeout(() => {
        func.apply(this, args);
        flag = true;
      }, delay);
    };
  }

  // 销毁
  public destroy() {
    this.death = true;
    this.stop = true;
    if (this.timer) {
      clearTimeout(this.timer);
      this.timer = undefined;
    }
  }

  // 开启
  public open() {
    if (!this.death) {
      this.stop = false;
    }
  }

  // 关闭
  public close() {
    this.stop = true;
  }
}

使用

<template>
  <div id="debounced-test">
    <v-button @click="handelClickByDebounced">防抖</v-button>
    <v-button @click="handelClickByThrottle" type="success">节流</v-button>
    <v-button @click="changeStopThrottle(throttle.stop)" type="warning">
      {{ throttle.stop ? '开启' : '关闭' }}节流
    </v-button>
    <v-button @click="destroyThrottle" type="danger">销毁节流函数</v-button>
  </div>
</template>

<script lang="ts">
import { Debounced, Throttle } from '@/utils'
import { Vue, Component } from 'vue-property-decorator'

@Component
export default class DebouncedTest extends Vue {
  private count: number = 1
  private debouncedUse: Function = new Debounced().use(this.request, 1000)
  private throttle = new Throttle()
  private throttleUse: Function = this.throttle.use(this.request, 1000)

  private request(params: any) {
    console.log('this的指向', this);
    console.log('参数', params);
    console.log(this.count++)
  }
  // 防抖调用
  private handelClickByDebounced() {
    this.debouncedUse(123)
  }
  // 节流调用
  private handelClickByThrottle() {
    this.throttleUse('截流函数')
  }
  // 停止 | 开启节流函数
  private changeStopThrottle(action: boolean) {
    action ? this.throttle.open() : this.throttle.close()
  }
  // 销毁节流函数
  private destroyThrottle() {
    this.throttle.destroy()
  }
}
</script>