微信小程序是数据驱动的应用，开发技术和vue、react和angular等mv*技术类似。在vue下可以用vue-resource、axios等模块进行http请求，但是在微信小程序上，http请求只支持wx.request(OBJECT)，所以我们需要对wx.request进行封装，实现http拦截器的功能。
第一步：创建一个request.js文件
第二步：确定http、upload和websocket前缀
第三步：封装wx.request
在请求发出前处理http地址、请求头和参数、在响应后解析返回值并做基本的逻辑判断，重点是使用Promise对象。
第四步：导出模块
第五步：使用request
const Request = require("/utils/request");//导入模块 Request.post("/api/xcxWxLogin", { //调用方法 code: res.code, encryptedData: resp.encryptedData, iv: resp.iv, shareId: share.shareId || "", salesmanId: share.salesmanId || "", source: share.source || "" }).then(res => { //成功回调 //todo }).catch(err => {}); //异常回调
第六步：拦截器完整代码
const apiHttp = "https://*****.com"; const socketHttp = "wss://*****.com/wss"; function fun(url, method, data, header) { data = data || {}; header = header || {}; let sessionId = wx.getStorageSync("UserSessionId"); if (sessionId) { if (!header || !header["SESSIONID"]) { header["SESSIONID"] = sessionId; } } wx.showNavigationBarLoading(); let promise = new Promise(function(resolve, reject) { wx.request({ url: apiHttp + url, header: header, data: data, method: method, success: function(res) { if (typeof res.data === "object") { if (res.data.status) { if (res.data.status === -200) { wx.showToast({ title: "为确保能向您提供最准确的服务，请退出应用重新授权", icon: "none" }); reject("请重新登录"); } else if (res.data.status === -201) { wx.showToast({ title: res.data.msg, icon: "none" }); setTimeout(function() { wx.navigateTo({ url: "/pages/user/supplement/supplement" }); }, 1000); reject(res.data.msg); } } } resolve(res); }, fail: reject, complete: function() { wx.hideNavigationBarLoading(); } }); }); return promise; } function upload(url, name, filePath) { let header = {}; let sessionId = wx.getStorageSync("UserSessionId"); //从缓存中拿该信息 if (sessionId) { if (!header || !header["SESSIONID"]) { header["SESSIONID"] = sessionId; //添加到请求头中 } } wx.showNavigationBarLoading(); let promise = new Promise(function(resolve, reject) { wx.uploadFile({ url: apiHttp + url, filePath: filePath, name: name, header: header, success: function(res) { resolve(res); }, fail: reject, complete: function() { wx.hideNavigationBarLoading(); } }); }); return promise; } module.exports = { apiHttp: apiHttp, socketHttp: socketHttp, "get": function(url, data, header) { return fun(url, "GET", data, header); }, "post": function(url, data, header) { return fun(url, "POST", data, header); }, upload: function(url, name, filePath) { return upload(url, name, filePath); } };