前言
在学习了之前的路由vue-router和状态管理vuex之后，就应该是网络交互了。就学习尤大推荐的axios了。刚好本人对网络请求这块除了会get、put、post和delete这四个方法之外知之甚少，刚好补全上。
注意：Vue官方推荐的网络通信库不再是vue-resource了，推荐使用axios。
为何放弃vue-resource？
尤大的原话：
最近团队讨论了一下，Ajax 本身跟 Vue 并没有什么需要特别整合的地方，使用 fetch polyfill 或是 axios、superagent 等等都可以起到同等的效果，vue-resource 提供的价值和其维护成本相比并不划算，所以决定在不久以后取消对 vue-resource 的官方推荐。已有的用户可以继续使用，但以后不再把 vue-resource 作为官方的 ajax 方案。
axios安装
npm:
bower:
Using cdn:
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<script src="https://unpkg.com/axios/dist/axios.min.js">script>
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基本使用方法
GET请求
// Make a request for a user with a given ID
axios.get('/user?ID=12345')
.then(function (response) {
console.log(response);
})
.catch(function (error) {
console.log(error);
});
// Optionally the request above could also be done as
axios.get('/user', {
params: {
ID: 12345
}
})
.then(function (response) {
console.log(response);
})
.catch(function (error) {
console.log(error);
});
POST请求
axios.post('/user', {
firstName: 'Fred',
lastName: 'Flintstone'
})
.then(function (response) {
console.log(response);
})
.catch(function (error) {
console.log(error);
});
同时执行多个请求
function getUserAccount() {
return axios.get('/user/12345');
}
function getUserPermissions() {
return axios.get('/user/12345/permissions');
}
axios.all([getUserAccount(), getUserPermissions()])
.then(axios.spread(function (acct, perms) {
// Both requests are now complete
}));
其实和其他的ajax库一样，基本用法都是差不多的。大家一看就知道怎么用。
axios API
可以直接通过config来完成请求
axios(config)
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axios({
method: 'post',
url: '/user/12345',
data: {
firstName: 'Fred',
lastName: 'Flintstone'
}
});
|
axios(url, [config])
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// Send a GET request (default method)
axios('/user/12345');
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请求方法别名
下面是axios支持的所有请求方法别名，便于各种请求。
注： [...]中的数据表示可以为空。url是ajax请求地址；data是提交的数据对象；config是配置对象，所有ajax配置都可以在config中实现。
- axios.request(config)
- axios.get(url[, config])
- axios.delete(url[, config])
- axios.head(url[, config])
- axios.post(url[, data[, config]])
- axios.put(url[, data[, config]])
- axios.patch(url[, data[, config]])
并发性
下列接口用于处理并发请求(同时处理多个多个request)
- axios.all(iterable)
- axios.spread(callback)
axios实例
可以用自定义的config创建一个axios实例
axios.create([config])
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var instance = axios.create({
baseURL: 'https://some-domain.com/api/',
timeout: 1000,
headers: {'X-Custom-Header': 'foobar'}
});
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实例方法
下面是实例的所有可用方法，方法中的config会与axios实例中的config合并。（实例可以将一些通用的config先配置好）
- axios#request(config)
- axios#get(url, [config])
- axios#delete(url, [config])
- axios#head(url, [config])
- axios#post(url[, data[, config]])
- axios#put(url[, data[, config]])
- axios#patch(url[, data[, config]])
Config
重点来了，来看看Config。
下面列出了config的所有配置项，其中之后url是必填的。当method没有指定方法，默认为GET。
{
// `url` is the server URL that will be used for the request
// 用来向服务器发送请求的url
url: '/user',
// `method` is the request method to be used when making the request
// 请求方法
method: 'get', // default
// `baseURL` will be prepended to `url` unless `url` is absolute.
// It can be convenient to set `baseURL` for an instance of axios to pass relative URLs
// to methods of that instance.
// 假如`url`不是绝对路径，那么向服务器发送请求的URL将是`baseURL + url`
baseURL: 'https://some-domain.com/api/',
// `transformRequest` allows changes to the request data before it is sent to the server
// This is only applicable for request methods 'PUT', 'POST', and 'PATCH'
// The last function in the array must return a string, an ArrayBuffer, or a Stream
transformRequest: [function (data) {
// Do whatever you want to transform the data
return data;
}],
// `transformResponse` allows changes to the response data to be made before
// it is passed to then/catch
transformResponse: [function (data) {
// Do whatever you want to transform the data
return data;
}],
// `headers` are custom headers to be sent
headers: {'X-Requested-With': 'XMLHttpRequest'},
// `params` are the URL parameters to be sent with the request
// Must be a plain object or a URLSearchParams object
params: {
ID: 12345
},
// `paramsSerializer` is an optional function in charge of serializing `params`
// (e.g. https://www.npmjs.com/package/qs, http://api.jquery.com/jquery.param/)
paramsSerializer: function(params) {
return Qs.stringify(params, {arrayFormat: 'brackets'})
},
// `data` is the data to be sent as the request body
// Only applicable for request methods 'PUT', 'POST', and 'PATCH'
// When no `transformRequest` is set, must be of one of the following types:
// - string, plain object, ArrayBuffer, ArrayBufferView, URLSearchParams
// - Browser only: FormData, File, Blob
// - Node only: Stream
data: {
firstName: 'Fred'
},
// `timeout` specifies the number of milliseconds before the request times out.
// If the request takes longer than `timeout`, the request will be aborted.
timeout: 1000,
// `withCredentials` indicates whether or not cross-site Access-Control requests
// should be made using credentials
withCredentials: false, // default
// `adapter` allows custom handling of requests which makes testing easier.
// Return a promise and supply a valid response (see [response docs](#response-api)).
adapter: function (config) {
/* ... */
},
// `auth` indicates that HTTP Basic auth should be used, and supplies credentials.
// This will set an `Authorization` header, overwriting any existing
// `Authorization` custom headers you have set using `headers`.
auth: {
username: 'janedoe',
password: 's00pers3cret'
},
// `responseType` indicates the type of data that the server will respond with
// options are 'arraybuffer', 'blob', 'document', 'json', 'text', 'stream'
responseType: 'json', // default
// `xsrfCookieName` is the name of the cookie to use as a value for xsrf token
xsrfCookieName: 'XSRF-TOKEN', // default
// `xsrfHeaderName` is the name of the http header that carries the xsrf token value
xsrfHeaderName: 'X-XSRF-TOKEN', // default
// `onUploadProgress` allows handling of progress events for uploads
onUploadProgress: function (progressEvent) {
// Do whatever you want with the native progress event
},
// `onDownloadProgress` allows handling of progress events for downloads
onDownloadProgress: function (progressEvent) {
// Do whatever you want with the native progress event
},
// `maxContentLength` defines the max size of the http response content allowed
maxContentLength: 2000,
// `validateStatus` defines whether to resolve or reject the promise for a given
// HTTP response status code. If `validateStatus` returns `true` (or is set to `null`
// or `undefined`), the promise will be resolved; otherwise, the promise will be
// rejected.
validateStatus: function (status) {
return status >= 200 && status < 300; // default
},
// `maxRedirects` defines the maximum number of redirects to follow in node.js.
// If set to 0, no redirects will be followed.
maxRedirects: 5, // default
// `httpAgent` and `httpsAgent` define a custom agent to be used when performing http
// and https requests, respectively, in node.js. This allows to configure options like
// `keepAlive` that are not enabled by default.
httpAgent: new http.Agent({ keepAlive: true }),
httpsAgent: new https.Agent({ keepAlive: true }),
// 'proxy' defines the hostname and port of the proxy server
// `auth` indicates that HTTP Basic auth should be used to connect to the proxy, and supplies credentials.
// This will set an `Proxy-Authorization` header, overwriting any existing `Proxy-Authorization` custom headers you have set using `headers`.
proxy: {
host: '127.0.0.1',
port: 9000,
auth: : {
username: 'mikeymike',
password: 'rapunz3l'
}
},
// `cancelToken` specifies a cancel token that can be used to cancel the request
// (see Cancellation section below for details)
cancelToken: new CancelToken(function (cancel) {
})
}
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分析Config
配置参数很多，我们一个一个来了解它们
- url —— 用来向服务器发送请求的url
- method —— 请求方法，默认是GET方法
- baseURL —— 基础URL路径，假如url不是绝对路径，如https://some-domain.com/api/v1/login?name=jack,那么向服务器发送请求的URL将会是baseURL + url。
- transformRequest —— transformRequest方法允许在请求发送到服务器之前修改该请求，此方法只适用于PUT、POST和PATCH方法中。而且，此方法最后必须返回一个string、ArrayBuffer或者Stream。
- transformResponse —— transformResponse方法允许在数据传递到then/catch之前修改response数据。此方法最后也要返回数据。
- headers —— 发送自定义Headers头文件，头文件中包含了http请求的各种信息。
- params —— params是发送请求的查询参数对象，对象中的数据会被拼接成url?param1=value1¶m2=value2。
- paramsSerializer —— params参数序列化器。
- data —— data是在发送POST、PUT或者PATCH请求的数据对象。
- timeout —— 请求超时设置，单位为毫秒
- withCredentials —— 表明是否有跨域请求需要用到证书
- adapter —— adapter允许用户处理更易于测试的请求。返回一个Promise和一个有效的response
- auth —— auth表明提供凭证用于完成http的身份验证。这将会在headers中设置一个Authorization授权信息。自定义Authorization授权要设置在headers中。
- responseType —— 表示服务器将返回响应的数据类型，有arraybuffer、blob、document、json、text、stream这6个类型，默认是json类似数据。
- xsrfCookieName —— 用作 xsrf token 值的 cookie 名称
- xsrfHeaderName —— 带有 xsrf token 值 http head 名称
- onUploadProgress —— 允许在上传过程中的做一些操作
- onDownloadProgress —— 允许在下载过程中的做一些操作
- maxContentLength —— 定义了接收到的response响应数据的最大长度。
- validateStatus —— validateStatus定义了根据HTTP响应状态码决定是否接收或拒绝获取到的promise。如果 validateStatus 返回 true (或设置为 null 或 undefined ),promise将被接收;否则,promise将被拒绝。
- maxRedirects —— maxRedirects定义了在node.js中redirect的最大值，如果设置为0，则没有redirect。
- httpAgent —— 定义在使用http请求时的代理
- httpsAgent —— 定义在使用https请求时的代理
- proxy —— proxy定义代理服务器的主机名和端口，auth
- cancelToken —— cancelToken定义一个 cancel token 用于取消请求
Response
当我们ajax获取数据成功后会返回一个response对象，它包含了以下内容：
{
// `data` is the response that was provided by the server
data: {},
// `status` is the HTTP status code from the server response
status: 200,
// `statusText` is the HTTP status message from the server response
statusText: 'OK',
// `headers` the headers that the server responded with
headers: {},
// `config` is the config that was provided to `axios` for the request
config: {}
}
response是通过promise的then方法来获取,具体使用方法如下：
axios.get('/user/12345')
.then(function(response) {
console.log(response.data);
console.log(response.status);
console.log(response.statusText);
console.log(response.headers);
console.log(response.config);
});
相对的，我们有时也会出现ajax报错，此时就会到我们的catch中去捕获异常error对象。
总结
以上就是这篇文章的全部内容了，希望本文的内容对大家的学习或者工作能带来一定的帮助，如果有疑问大家可以留言交流，谢谢大家对脚本之家的支持。
原文链接：http://www.jianshu.com/p/8e5fb763c3d7?winzoom=1
