ES6对象中的setInterval

Question

我有以下对象。我一直工作到使用setinterval。 我意识到this成为对象timeout

class test{
    constructor(){
        this.counter = 0
    }
    startCounter(){
        this.increment()
       setInterval(this.increment, 1000)
    }
    increment(){
        this.counter++
        console.log(this.counter)
    }

}

var t = new test()
t.startCounter()

输出：

1
NaN
NaN
NaN
NaN
NaN
NaN

How to access the correct `this` inside a callback?建议我使用var self = this，但ES6不支持私有变量

Answer 1

请尝试以下操作：

class test{
    constructor(){
        this.counter = 0
    }
    startCounter(){
        this.increment()
       setInterval(this.increment.bind(this), 1000)
    }
    increment(){
        this.counter++
        console.log(this.counter)
    }

}

var t = new test()
t.startCounter()