Vue中监听窗口关闭事件，并在窗口关闭前发送请求

    mounted() {
      window.addEventListener('beforeunload', e => this.beforeunloadHandler(e))
      window.addEventListener('unload', e => this.unloadHandler(e))
    },
    destroyed() {
      window.removeEventListener('beforeunload', e => this.beforeunloadHandler(e))
      window.removeEventListener('unload', e => this.unloadHandler(e))
    },
    methods: {
      beforeunloadHandler(){
        this._beforeUnload_time=new Date().getTime();
      },
      unloadHandler(e){
        this._gap_time=new Date().getTime()-this._beforeUnload_time;
        debugger
        //判断是窗口关闭还是刷新
        if(this._gap_time<=5){
			//处理的事情
        }
      },
}