利用promise封装ajax,axios过程

封装ajax

  
  
var url = 'https://hq.tigerbrokers.com/fundamental/finance_calendar/getType/2017-02-26/2017-06-10';

// 封装一个get请求的方法
function getJSON(url) {
return new Promise( function(resolve, reject) {
var XHR = new XMLHttpRequest();
XHR.open( 'GET', url, true);
XHR.send();

XHR.onreadystatechange = function() {
if (XHR.readyState == 4) {
if (XHR.status == 200) {
try {
var response = JSON.parse(XHR.responseText);
resolve(response);
} catch (e) {
reject(e);
}
} else {
reject( new Error(XHR.statusText));
}
}
}
})
}

getJSON(url).then( resp => console.log(resp));
  
  

封装axios 

  
  
​
function myGet(url, params) {
return new Promise( (resolve, reject) => {
axios.get(url, params).then( function (response) {
resolve(response.data)
})
.catch( function (err) {
reject(err)
})
})
}

myGet(url,params).then( function(data){ console.log(data)}).catch( function(){})

封装ajax