打字稿编译错误-“类型…的值无法通过类型…编制索引”

Question

Using typescript 2.0.6.0

I have an interface defined:

interface indexesWorkData {
    pointInTime: number;
    numberOfIndexesWorking: number;
}

This is my class:

class work {         
    indexesWork: Array<indexesWorkData> = [];

    pushRange(startTime: number, endTime: number) {

        let indexStart = this.indexesWork.findIndex(x => x.pointInTime >= someNumber);
        if (this.indexesWork[indexStart].pointInTime === anotherNumber) {
            // Do stuff
        } 
    }
}

I get compilation error: "Value of type indexesWorkData[] is not indexable by type indexesWorkData" for trying to access this.indexesWork[indexStart ]

But at runtime it works and indexStart has correct value.

Why is that ?

Answer 1

您能否尝试明确告诉编译器有关indexStart的类型？

let indexStart: number = <number>this.indexesWork.findIndex(x => x.pointInTime >= someNumber);