Cross-domain error message:
Fetch API cannot load https://xxx.com/api. Response to preflight request doesn't pass access control check: The value of the 'Access-Control-Allow-Credentials' header in the response is '' which must be 'true' when the request's credentials mode is 'include'. Origin 'https://xxx.com' is therefore not allowed access.
Method1: pure js
export function Cors(url) { return new Promise((resolve, reject) => { const xhr = new XMLHttpRequest(); xhr.open('GET', url, true); xhr.withCredentials = true; // Set to run cross-domain operations xhr.send(); xhr.onload = () => { const text = xhr.responseText; if (xhr.status === 200) { resolve(JSON.parse(text)); } else { let error = new Error(text); error.response = xhr; reject(error); } }; }); }
Methods2:jQuery版
$.ajax({ url : 'xxx', xhrFields: { withCredentials: true // Set to run cross-domain operations }, success : function(data) { console.log(data); } });
Methods3: fetch (incompatible with some browsers, not recommended)
export function Get(url) { const config = { method: 'get', headers: { 'Accept': 'application/json', 'Content-Type': 'application/json' }, credentials: 'include' }; return fetch(url, config) .then(checkStatus) .then(parseJSON); }