Fetch API, need to deal with two promises to get the response data in JSON Object property. While axios result into JSON object. Also error handling is different in fetch, as it does not handle server side error in the catch block, the Promise returned from fetch() won’t reject on HTTP error status even if the response is an HTTP 404 or 500. Instead, it will resolve normally (with ok status set to false), and it will only reject on network failure or if anything prevented the request from completing. While in axios you can catch all error in catch block.

我会说更好的使用axios，直接处理拦截器，头配置，设置cookie和错误处理。

请参考这个

Axios是一个基于承诺的HTTP客户端库，而Fetch是一个用于发出API请求的javascript API。

主要区别是浏览器支持:Axios支持包括IE在内的所有浏览器，而Fetch只支持最新的浏览器，IE不支持。

参考链接:https://github.com/axios/axios浏览器支持

https://caniuse.com/fetch

与获取API相比，Axios具有更好的错误处理。Axios可以抛出400到500个范围的状态代码错误，而在fetch API中，您需要手动处理这些错误。 更多信息请访问:https://bariablogger.in/f/axios-vs-fetch-react

对于fetch，我们需要处理两个承诺。使用axios，我们可以直接访问响应对象数据属性中的JSON结果。

fetch API和axios API之间还有一个主要区别

在使用service worker时，只有当您想拦截HTTP请求时才必须使用fetch API 当使用service worker在PWA中执行缓存时，如果你使用axios API(它只适用于fetch API)，你将无法缓存。

除了……我在测试中使用了各种lib，并注意到它们对4xx请求的不同处理。在这种情况下，我的测试返回一个json对象，响应为400。这是3个流行的libs处理响应的方式:

// request-promise-native
const body = request({ url: url, json: true })
const res = await t.throws(body);
console.log(res.error)


// node-fetch
const body = await fetch(url)
console.log(await body.json())


// Axios
const body = axios.get(url)
const res = await t.throws(body);
console.log(res.response.data)

有趣的是，request-promise-native和axios在4xx响应上抛出，而节点获取则不会抛出。fetch还使用了json解析的promise。

Fetch和Axios在功能上非常相似，但为了更多的向后兼容性，Axios似乎工作得更好(例如，Fetch在IE 11中不能工作，请查看这篇文章)。

此外，如果您使用JSON请求，以下是我偶然发现的一些差异。

获取JSON post请求

let url = 'https://someurl.com';
let options = {
            method: 'POST',
            mode: 'cors',
            headers: {
                'Accept': 'application/json',
                'Content-Type': 'application/json;charset=UTF-8'
            },
            body: JSON.stringify({
                property_one: value_one,
                property_two: value_two
            })
        };
let response = await fetch(url, options);
let responseOK = response && response.ok;
if (responseOK) {
    let data = await response.json();
    // do something with data
}

Axios JSON post请求

let url = 'https://someurl.com';
let options = {
            method: 'POST',
            url: url,
            headers: {
                'Accept': 'application/json',
                'Content-Type': 'application/json;charset=UTF-8'
            },
            data: {
                property_one: value_one,
                property_two: value_two
            }
        };
let response = await axios(options);
let responseOK = response && response.status === 200 && response.statusText === 'OK';
if (responseOK) {
    let data = await response.data;
    // do something with data
}

So:

Fetch's body = Axios' data Fetch's body has to be stringified, Axios' data contains the object Fetch has no url in request object, Axios has url in request object Fetch request function includes the url as parameter, Axios request function does not include the url as parameter. Fetch request is ok when response object contains the ok property, Axios request is ok when status is 200 and statusText is 'OK' To get the json object response: in fetch call the json() function on the response object, in Axios get data property of the response object.