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异步函数的异常处理

 对于异步函数, 简单的try-catch并不能直接捕捉到。

比如说

function func1 () {

    try {

        func2()

    } catch (error) {

    }

}


function func2() {

    setTimeout(function () {

        throw new Error("error")

    }, 1000)

}


这里就无法catch到func2里面throw的error


所以应该是func2返回一个封装在Promise里面的函数，在func1里面用await来接收。因为await是对一个表达式求值。如果await后面是promise的话，就会等待Promise返回才执行。



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