來自：https://www.jianshu.com/p/180957762852 侵刪

beforeMount() {
    //車輛進出設置定時器，每3秒刷新一次
    var self = this;
    clearInterval(timer);
    let timer = setInterval(_getCarPeopleStreamByEntraceBottom, 3000)

    function _getCarPeopleStreamByEntraceBottom() {
        //生成隨機數用來測試
        let totelNumber = new Array(8);
        
 
for (let i = 0; i < totelNumber.length; i++) {
            totelNumber[i] = Math.ceil(Math.random() * 10) - 1
        };

        let data = {
            carInNumber: totelNumber[0],
            carOutNumber: totelNumber[1]
        };
        self.southPassagewayData = data;
    }
    _getCarPeopleStreamByEntraceBottom();
},
 

vue 使用定時器setInterval