React中定时器的使用及清除

注意点

1、定时器中this一般指向为window对象

2、react箭头函数中定时器中也可以使用this,为当前class对象

 

实践：

1、定时器赋值给全局变量，异步动作后清除

class TopoPanel extends Component {
    constructor(props) {

    }
    startGetTopoDataInterval = () => {
        this.startGetTopoDataInterval = setInterval(this.getTopoDataIntervalTask,1000);
    }

    getTopoDataIntervalTask = () =>{
        let isDataOK = this.getTopoDataAndSetState();
        if (isDataOK) {
            this.clearGetTopoDataInterval();
        }
    }

    clearGetTopoDataInterval = () => {
        clearInterval(this.startGetTopoDataInterval);
    }

    getTopoDataAndSetState = () => {
        let cacheData = xxx;
        if (cacheData) {
            xxx;
        }
        else {
            xxx;
            return false;
        }

        return true;
    }

}

2、定时器定义为局部变量

class Panel extends Component {
    constructor(props) {

    }

    startDrawLoadInterval = (loadData) => {
        let drawLoadInterval = setInterval((loadData)=>{
            if (xxx) {
                xxx;
                clearInterval(drawLoadInterval);
            }
        },1000);
    }

}