处理来自 setTimeout 的错误

问题描述

关于在 setTimeout 中 try-catch for 函数的简单问题

Simple question about try-catch for function in setTimeout

try {
    setTimeout(function () {
        throw new Error('error!');
    }, 300)
} catch (e) {
    console.log('eeee!')
    console.log(e)
}

为什么不使用 catch-block?

Why dont work catch-block?

关于这个我能读到什么?

What I can read about this?

P.S:关于处理此类错误的可能性的问题.不要回答关于承诺的问题

P.S: Question about possibility of handling errors like this. Dont answer about promises

推荐答案

计划使用 setTimeout 运行的函数在主循环中执行，在产生它们的代码体之外.

Functions scheduled to run with setTimeout are executed in the main loop, outside the body of code that originated them.

要处理错误，请将 try-catch 放在 setTimeout 处理程序中:

To handle errors, put the try-catch inside the setTimeout handler:

setTimeout(function () {
  try {
    throw new Error('error!');
  } catch (e) {
    console.error(e);
  }
}, 300)

如果您需要从名为 setTimeout 的块访问 Error 对象，请使用 Promises:

If you need to access the Error object from block that called setTimeout, use Promises:

const promise = new Promise((resolve, reject) => {
  setTimeout(function () {
    try {
      throw new Error('error!');
      resolve(); // if the previous line didn't always throw

    } catch (e) {
      reject(e)
    }
  }, 300)
})

promise
  .then(result => console.log("Ok " + result))
  .catch(error => console.error("Ouch " + error))

上面的这个例子并不是用 Promise 处理这种情况的最优雅的方式.相反，实现一个 delay(ms) 函数，如下所示:

This example above is not the most elegant way of handling the case with a Promise. Instead, implement a delay(ms) function like this:

function delay(ms) {
  return new Promise(resolve => setTimeout(resolve, ms))
}

然后调用

delay(300).then(myFunction).catch(handleError)

这篇关于处理来自 setTimeout 的错误的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！