这篇文章主要介绍“Javascript中async与await的捕捉错误怎么理解”，在日常操作中，相信很多人在Javascript中async与await的捕捉错误怎么理解问题上存在疑惑，小编查阅了各式资料，整理出简单好用的操作方法，希望对大家解答”Javascript中async与await的捕捉错误怎么理解”的疑惑有所帮助！接下来，请跟着小编一起来学习吧！
async与await捕捉错误
正常的输出时
<template>
<div class="hello">
</div>
</template>
<script>
export default {
name: 'HelloWorld',
created() {
this.init()
},
methods: {
init() {
let p1 = new Promise((resolve) => {
setTimeout(() => {
resolve(666)
}, 1000)
})
async function run() {
let res = await p1
console.log('res', res)
}
run()
// 正常的调用时候：log输出 666
},
},
}
</script>
try catch捕捉错误
<template>
<div class="hello">
<h2>{{ msg }}</h2>
<p>
For a guide and recipes on how to configure / customize this project,<br />
check out the
<a href="https://cli.vuejs.org" target="_blank" rel="noopener">vue-cli documentation</a>.
</p>
<h4>Installed CLI Plugins</h4>
<ul>
<li><a href="https://github.com/vuejs/vue-cli/tree/dev/packages/%40vue/cli-plugin-babel" target="_blank" rel="noopener">babel</a></li>
<li><a href="https://github.com/vuejs/vue-cli/tree/dev/packages/%40vue/cli-plugin-eslint" target="_blank" rel="noopener">eslint</a></li>
</ul>
<h4>Essential Links</h4>
<ul>
<li><a href="https://vuejs.org" target="_blank" rel="noopener">Core Docs</a></li>
<li><a href="https://forum.vuejs.org" target="_blank" rel="noopener">Forum</a></li>
<li><a href="https://chat.vuejs.org" target="_blank" rel="noopener">Community Chat</a></li>
<li><a href="https://twitter.com/vuejs" target="_blank" rel="noopener">Twitter</a></li>
<li><a href="https://news.vuejs.org" target="_blank" rel="noopener">News</a></li>
</ul>
<h4>Ecosystem</h4>
<ul>
<li><a href="https://router.vuejs.org" target="_blank" rel="noopener">vue-router</a></li>
<li><a href="https://vuex.vuejs.org" target="_blank" rel="noopener">vuex</a></li>
<li><a href="https://github.com/vuejs/vue-devtools#vue-devtools" target="_blank" rel="noopener">vue-devtools</a></li>
<li><a href="https://vue-loader.vuejs.org" target="_blank" rel="noopener">vue-loader</a></li>
<li><a href="https://github.com/vuejs/awesome-vue" target="_blank" rel="noopener">awesome-vue</a></li>
</ul>
</div>
</template>
<script>
export default {
name: 'HelloWorld',
props: {
msg: String,
},
created() {
this.init()
},
methods: {
init() {
let p1 = new Promise((reject) => {
setTimeout(() => {
reject(new Error('错误了哦'))
}, 1000)
})
async function run() {
try {
let res = await p1
console.log('res', res)
} catch (error) {
console.log('error', error)
}
}
run()
// 报错运行 res Error: 错误了哦
},
},
}
</script>
多个异步嵌套时
没有try {} catch {} 捕捉错误的
<template>
</template>
<script>
export default {
name: 'HelloWorld',
props: {
msg: String,
},
created() {
this.init()
},
methods: {
init() {
let p1 = new Promise((resolve) => {
setTimeout(() => {
// reject(new Error('错误了哦'))
resolve(1)
}, 1000)
})
let p2 = function (arg) {
return new Promise((reject) => {
setTimeout(() => {
console.log('arg', arg)
reject(new Error('错误了哦'))
}, 1000)
})
}
async function run() {
const res1 = await p1
console.log('res1', res1) // 1
const res2 = await p2(res1)
console.log('res2', res2) // res2 Error: 错误了哦
}
run()
},
},
}
</script>
适使用try{} catch {} 捕捉错误的
<template>
<div>HelloWorld</div>
</template>
<script>
export default {
name: 'HelloWorld',
components: {},
data() {
return {}
},
created() {
this.init()
},
methods: {
init() {
let p1 = new Promise((resolve) => {
setTimeout(() => {
// reject(new Error('错误了哦'))
resolve(1)
}, 1000)
})
let p2 = function (arg) {
return new Promise((reject) => {
setTimeout(() => {
console.log('arg', arg)
reject(new Error('错误了哦'))
}, 1000)
})
}
async function run() {
try {
var res1 = await p1
console.log('res1', res1)
} catch (error) {
return new Error('error1', error)
}
try {
const res2 = await p2(res1)
console.log('res2', res2)
} catch (error) {
return new Error('error2', error)
}
}
run()
},
},
}
</script>
<style lang="scss" scoped></style>
效果
await-to-js
await-to-js官网
异步嵌套使用了try，代码相对不够智能
-
特别使用第三方的npm包 await-to-js
-
作用：无需 try-catch 即可轻松处理错误的异步等待包装器
-
下载：
yarn add await-to-js -S -
使用
<template>
<div>HelloWorld</div>
</template>
<script>
import awaitTo from 'await-to-js'
export default {
name: 'HelloWorld',
components: {},
data() {
return {}
},
created() {
this.init()
},
methods: {
init() {
let p1 = new Promise((resolve) => {
setTimeout(() => {
// reject(new Error('错误了哦'))
resolve(1)
}, 1000)
})
let p2 = function (arg) {
return new Promise((reject) => {
setTimeout(() => {
console.log('arg', arg)
reject(new Error('错误了哦'))
}, 1000)
})
}
async function run() {
const [err, res1] = await awaitTo(p1)
if (err) throw new Error('错误1')
console.log('res1', res1)
const [err2, res2] = await awaitTo(p2(res1))
if (err2) throw new Error('错误2')
console.log('res2', res2)
}
run()
},
},
}
</script>
<style lang="scss" scoped></style>
效果：
到此，关于“Javascript中async与await的捕捉错误怎么理解”的学习就结束了，希望能够解决大家的疑惑。理论与实践的搭配能更好的帮助大家学习，快去试试吧！若想继续学习更多相关知识，请继续关注本站网站，小编会继续努力为大家带来更多实用的文章！
