封装统一请求的目的：在请求时有时会返回不同的返回码进行不同的数据处理，比如：返回正常时，进行正常操作，如果返回了异常，那么就需要进行不同的处理了，由于每次请求都可能出现各种返回码，所以进行请求封装，进行统一异常处理。
在小程序中提供的请求：
wx.request({
url: url,
data: params,
method: 'POST',
header: { 'content-type': 'application/x-www-form-urlencoded' },
success: function (result){
}})
默认是一个异步请求，我在封装时采用封装同步请求的方式。
在这里我使用了ES6中的 es6-promise，Promise的特点是同步操作，可以创建数个Promise对象，把需要同步的代码封装到Promise对象中
let promisevariable = new Promise(function (resolve, reject) {
wx.request({
url: servser+url,
data: params,
method: 'POST',
header: { 'content-type': 'application/x-www-form-urlencoded' },
success: function (result){
var status = result.statusCode;
if(status == 500){
//程序抛出异常
var exception = result.data.exception;
var msg = result.data.message;
var path = result.data.path;
wx.showToast({
title: exception+"\r\n"+msg+"\n\r"+path,
icon: 'loading',
duration: 1000
});
resolve(null);
return ;
}
if(status != 200){
//系统未知异常
var msg = result.data.error;
var path = result.data.path;
wx.showToast({
title: msg+"\n\r"+path,
icon: 'loading',
duration: 1000
});
resolve(null);
return ;
} //自定义异常
var sta = result.data.status;
if(sta != 200){
var msg = result.data.message;
wx.showToast({
title: msg,
icon: 'loading',
duration: 1000
});
resolve(null);
return ;
}
resolve(result);
//这里就是每个Promise对象的结果
}
});
});
然后把该对象按顺序放到一个数组中，使用Promise提供的方法 Promise.all
Promise.all([数组对象]).then(function(values) {
//这里就可以顺序执行并得到每个结果
console.log(values);
});
---------------------
//引入Promise
var Promise = require('./es6-promise.auto.js');
//获取服务器地址
var servser = getApp().data.servsers;
console.log(servser);
//默认请求
function sendRequest(url,params){
let promisevariable = new Promise(function (resolve, reject) {
wx.request({
url: servser+url,
data: params,
method: 'POST',
header: {
'content-type': 'application/x-www-form-urlencoded'
},
success: function (result){
var status = result.statusCode;
if(status == 500){
//程序抛出异常
var exception = result.data.exception;
var msg = result.data.message;
var path = result.data.path;
wx.showToast({
title: exception+"\r\n"+msg+"\n\r"+path,
icon: 'loading',
duration: 1000
});
resolve(null);
return ;
}
if(status != 200){
//系统未知异常
var msg = result.data.error;
var path = result.data.path;
wx.showToast({
title: msg+"\n\r"+path,
icon: 'loading',
duration: 1000
});
resolve(null);
return ;
}
//自定义异常
var sta = result.data.status;
if(sta != 200){
var msg = result.data.message;
wx.showToast({
title: msg,
icon: 'loading',
duration: 1000
});
resolve(null);
return ;
}
resolve(result);
}
});
});
return promisevariable;
}
//暴露公共访问接口
module.exports = {
sendRequest: sendRequest,//公布公共请求接口
}
使用：
var url = "/home/test";
var params = {msg: '哈哈哈'}
requestHandler.sendRequest(url,params).then(values => {
console.log(values.data)
this.setData({
result : values.data
});
})
es6-promise.auto.js
(function (global, factory) {
typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
typeof define === 'function' && define.amd ? define(factory) :
(global.ES6Promise = factory());
}(this, (function () { 'use strict';
function objectOrFunction(x) {
var type = typeof x;
return x !== null && (type === 'object' || type === 'function');
}
function isFunction(x) {
return typeof x === 'function';
}
var _isArray = void 0;
if (Array.isArray) {
_isArray = Array.isArray;
} else {
_isArray = function (x) {
return Object.prototype.toString.call(x) === '[object Array]';
};
}
var isArray = _isArray;
var len = 0;
var vertxNext = void 0;
var customSchedulerFn = void 0;
var asap = function asap(callback, arg) {
queue[len] = callback;
queue[len + 1] = arg;
len += 2;
if (len === 2) {
// If len is 2, that means that we need to schedule an async flush.
// If additional callbacks are queued before the queue is flushed, they
// will be processed by this flush that we are scheduling.
if (customSchedulerFn) {
customSchedulerFn(flush);
} else {
scheduleFlush();
}
}
};
function setScheduler(scheduleFn) {
customSchedulerFn = scheduleFn;
}
function setAsap(asapFn) {
asap = asapFn;
}
var browserWindow = typeof window !== 'undefined' ? window : undefined;
var browserGlobal = browserWindow || {};
var BrowserMutationObserver = browserGlobal.MutationObserver || browserGlobal.WebKitMutationObserver;
var isNode = typeof self === 'undefined' && typeof process !== 'undefined' && {}.toString.call(process) === '[object process]';
// test for web worker but not in IE10
var isWorker = typeof Uint8ClampedArray !== 'undefined' && typeof importScripts !== 'undefined' && typeof MessageChannel !== 'undefined';
// node
function useNextTick() {
// node version 0.10.x displays a deprecation warning when nextTick is used recursively
// see https://github.com/cujojs/when/issues/410 for details
return function () {
return process.nextTick(flush);
};
}
// vertx
function useVertxTimer() {
if (typeof vertxNext !== 'undefined') {
return function () {
vertxNext(flush);
};
}
return useSetTimeout();
}
function useMutationObserver() {
var iterations = 0;
var observer = new BrowserMutationObserver(flush);
var node = document.createTextNode('');
observer.observe(node, { characterData: true });
return function () {
node.data = iterations = ++iterations % 2;
};
}
// web worker
function useMessageChannel() {
var channel = new MessageChannel();
channel.port1.onmessage = flush;
return function () {
return channel.port2.postMessage(0);
};
}
function useSetTimeout() {
// Store setTimeout reference so es6-promise will be unaffected by
// other code modifying setTimeout (like sinon.useFakeTimers())
var globalSetTimeout = setTimeout;
return function () {
return globalSetTimeout(flush, 1);
};
}
var queue = new Array(1000);
function flush() {
for (var i = 0; i < len; i += 2) {
var callback = queue[i];
var arg = queue[i + 1];
callback(arg);
queue[i] = undefined;
queue[i + 1] = undefined;
}
len = 0;
}
function attemptVertx() {
try {
var vertx = Function('return this')().require('vertx');
vertxNext = vertx.runOnLoop || vertx.runOnContext;
return useVertxTimer();
} catch (e) {
return useSetTimeout();
}
}
var scheduleFlush = void 0;
// Decide what async method to use to triggering processing of queued callbacks:
if (isNode) {
scheduleFlush = useNextTick();
} else if (BrowserMutationObserver) {
scheduleFlush = useMutationObserver();
} else if (isWorker) {
scheduleFlush = useMessageChannel();
} else if (browserWindow === undefined && typeof require === 'function') {
scheduleFlush = attemptVertx();
} else {
scheduleFlush = useSetTimeout();
}
function then(onFulfillment, onRejection) {
var parent = this;
var child = new this.constructor(noop);
if (child[PROMISE_ID] === undefined) {
makePromise(child);
}
var _state = parent._state;
if (_state) {
var callback = arguments[_state - 1];
asap(function () {
return invokeCallback(_state, child, callback, parent._result);
});
} else {
subscribe(parent, child, onFulfillment, onRejection);
}
return child;
}
function resolve$1(object) {
var Constructor = this;
if (object && typeof object === 'object' && object.constructor === Constructor) {
return object;
}
var promise = new Constructor(noop);
resolve(promise, object);
return promise;
}
var PROMISE_ID = Math.random().toString(36).substring(2);
function noop() {}
var PENDING = void 0;
var FULFILLED = 1;
var REJECTED = 2;
var TRY_CATCH_ERROR = { error: null };
function selfFulfillment() {
return new TypeError("You cannot resolve a promise with itself");
}
function cannotReturnOwn() {
return new TypeError('A promises callback cannot return that same promise.');
}
function getThen(promise) {
try {
return promise.then;
} catch (error) {
TRY_CATCH_ERROR.error = error;
return TRY_CATCH_ERROR;
}
}
function tryThen(then$$1, value, fulfillmentHandler, rejectionHandler) {
try {
then$$1.call(value, fulfillmentHandler, rejectionHandler);
} catch (e) {
return e;
}
}
function handleForeignThenable(promise, thenable, then$$1) {
asap(function (promise) {
var sealed = false;
var error = tryThen(then$$1, thenable, function (value) {
if (sealed) {
return;
}
sealed = true;
if (thenable !== value) {
resolve(promise, value);
} else {
fulfill(promise, value);
}
}, function (reason) {
if (sealed) {
return;
}
sealed = true;
reject(promise, reason);
}, 'Settle: ' + (promise._label || ' unknown promise'));
if (!sealed && error) {
sealed = true;
reject(promise, error);
}
}, promise);
}
function handleOwnThenable(promise, thenable) {
if (thenable._state === FULFILLED) {
fulfill(promise, thenable._result);
} else if (thenable._state === REJECTED) {
reject(promise, thenable._result);
} else {
subscribe(thenable, undefined, function (value) {
return resolve(promise, value);
}, function (reason) {
return reject(promise, reason);
});
}
}
function handleMaybeThenable(promise, maybeThenable, then$$1) {
if (maybeThenable.constructor === promise.constructor && then$$1 === then && maybeThenable.constructor.resolve === resolve$1) {
handleOwnThenable(promise, maybeThenable);
} else {
if (then$$1 === TRY_CATCH_ERROR) {
reject(promise, TRY_CATCH_ERROR.error);
TRY_CATCH_ERROR.error = null;
} else if (then$$1 === undefined) {
fulfill(promise, maybeThenable);
} else if (isFunction(then$$1)) {
handleForeignThenable(promise, maybeThenable, then$$1);
} else {
fulfill(promise, maybeThenable);
}
}
}
function resolve(promise, value) {
if (promise === value) {
reject(promise, selfFulfillment());
} else if (objectOrFunction(value)) {
handleMaybeThenable(promise, value, getThen(value));
} else {
fulfill(promise, value);
}
}
function publishRejection(promise) {
if (promise._onerror) {
promise._onerror(promise._result);
}
publish(promise);
}
function fulfill(promise, value) {
if (promise._state !== PENDING) {
return;
}
promise._result = value;
promise._state = FULFILLED;
if (promise._subscribers.length !== 0) {
asap(publish, promise);
}
}
function reject(promise, reason) {
if (promise._state !== PENDING) {
return;
}
promise._state = REJECTED;
promise._result = reason;
asap(publishRejection, promise);
}
function subscribe(parent, child, onFulfillment, onRejection) {
var _subscribers = parent._subscribers;
var length = _subscribers.length;
parent._onerror = null;
_subscribers[length] = child;
_subscribers[length + FULFILLED] = onFulfillment;
_subscribers[length + REJECTED] = onRejection;
if (length === 0 && parent._state) {
asap(publish, parent);
}
}
function publish(promise) {
var subscribers = promise._subscribers;
var settled = promise._state;
if (subscribers.length === 0) {
return;
}
var child = void 0,
callback = void 0,
detail = promise._result;
for (var i = 0; i < subscribers.length; i += 3) {
child = subscribers[i];
callback = subscribers[i + settled];
if (child) {
invokeCallback(settled, child, callback, detail);
} else {
callback(detail);
}
}
promise._subscribers.length = 0;
}
function tryCatch(callback, detail) {
try {
return callback(detail);
} catch (e) {
TRY_CATCH_ERROR.error = e;
return TRY_CATCH_ERROR;
}
}
function invokeCallback(settled, promise, callback, detail) {
var hasCallback = isFunction(callback),
value = void 0,
error = void 0,
succeeded = void 0,
failed = void 0;
if (hasCallback) {
value = tryCatch(callback, detail);
if (value === TRY_CATCH_ERROR) {
failed = true;
error = value.error;
value.error = null;
} else {
succeeded = true;
}
if (promise === value) {
reject(promise, cannotReturnOwn());
return;
}
} else {
value = detail;
succeeded = true;
}
if (promise._state !== PENDING) {
// noop
} else if (hasCallback && succeeded) {
resolve(promise, value);
} else if (failed) {
reject(promise, error);
} else if (settled === FULFILLED) {
fulfill(promise, value);
} else if (settled === REJECTED) {
reject(promise, value);
}
}
function initializePromise(promise, resolver) {
try {
resolver(function resolvePromise(value) {
resolve(promise, value);
}, function rejectPromise(reason) {
reject(promise, reason);
});
} catch (e) {
reject(promise, e);
}
}
var id = 0;
function nextId() {
return id++;
}
function makePromise(promise) {
promise[PROMISE_ID] = id++;
promise._state = undefined;
promise._result = undefined;
promise._subscribers = [];
}
function validationError() {
return new Error('Array Methods must be provided an Array');
}
var Enumerator = function () {
function Enumerator(Constructor, input) {
this._instanceConstructor = Constructor;
this.promise = new Constructor(noop);
if (!this.promise[PROMISE_ID]) {
makePromise(this.promise);
}
if (isArray(input)) {
this.length = input.length;
this._remaining = input.length;
this._result = new Array(this.length);
if (this.length === 0) {
fulfill(this.promise, this._result);
} else {
this.length = this.length || 0;
this._enumerate(input);
if (this._remaining === 0) {
fulfill(this.promise, this._result);
}
}
} else {
reject(this.promise, validationError());
}
}
Enumerator.prototype._enumerate = function _enumerate(input) {
for (var i = 0; this._state === PENDING && i < input.length; i++) {
this._eachEntry(input[i], i);
}
};
Enumerator.prototype._eachEntry = function _eachEntry(entry, i) {
var c = this._instanceConstructor;
var resolve$$1 = c.resolve;
if (resolve$$1 === resolve$1) {
var _then = getThen(entry);
if (_then === then && entry._state !== PENDING) {
this._settledAt(entry._state, i, entry._result);
} else if (typeof _then !== 'function') {
this._remaining--;
this._result[i] = entry;
} else if (c === Promise$2) {
var promise = new c(noop);
handleMaybeThenable(promise, entry, _then);
this._willSettleAt(promise, i);
} else {
this._willSettleAt(new c(function (resolve$$1) {
return resolve$$1(entry);
}), i);
}
} else {
this._willSettleAt(resolve$$1(entry), i);
}
};
Enumerator.prototype._settledAt = function _settledAt(state, i, value) {
var promise = this.promise;
if (promise._state === PENDING) {
this._remaining--;
if (state === REJECTED) {
reject(promise, value);
} else {
this._result[i] = value;
}
}
if (this._remaining === 0) {
fulfill(promise, this._result);
}
};
Enumerator.prototype._willSettleAt = function _willSettleAt(promise, i) {
var enumerator = this;
subscribe(promise, undefined, function (value) {
return enumerator._settledAt(FULFILLED, i, value);
}, function (reason) {
return enumerator._settledAt(REJECTED, i, reason);
});
};
return Enumerator;
}();
function all(entries) {
return new Enumerator(this, entries).promise;
}
function race(entries) {
var Constructor = this;
if (!isArray(entries)) {
return new Constructor(function (_, reject) {
return reject(new TypeError('You must pass an array to race.'));
});
} else {
return new Constructor(function (resolve, reject) {
var length = entries.length;
for (var i = 0; i < length; i++) {
Constructor.resolve(entries[i]).then(resolve, reject);
}
});
}
}
function reject$1(reason) {
var Constructor = this;
var promise = new Constructor(noop);
reject(promise, reason);
return promise;
}
function needsResolver() {
throw new TypeError('You must pass a resolver function as the first argument to the promise constructor');
}
function needsNew() {
throw new TypeError("Failed to construct 'Promise': Please use the 'new' operator, this object constructor cannot be called as a function.");
}
var Promise$2 = function () {
function Promise(resolver) {
this[PROMISE_ID] = nextId();
this._result = this._state = undefined;
this._subscribers = [];
if (noop !== resolver) {
typeof resolver !== 'function' && needsResolver();
this instanceof Promise ? initializePromise(this, resolver) : needsNew();
}
}
Promise.prototype.catch = function _catch(onRejection) {
return this.then(null, onRejection);
};
Promise.prototype.finally = function _finally(callback) {
var promise = this;
var constructor = promise.constructor;
return promise.then(function (value) {
return constructor.resolve(callback()).then(function () {
return value;
});
}, function (reason) {
return constructor.resolve(callback()).then(function () {
throw reason;
});
});
};
return Promise;
}();
Promise$2.prototype.then = then;
Promise$2.all = all;
Promise$2.race = race;
Promise$2.resolve = resolve$1;
Promise$2.reject = reject$1;
Promise$2._setScheduler = setScheduler;
Promise$2._setAsap = setAsap;
Promise$2._asap = asap;
function polyfill() {
var local = void 0;
if (typeof global !== 'undefined') {
local = global;
} else if (typeof self !== 'undefined') {
local = self;
} else {
try {
local = Function('return this')();
} catch (e) {
throw new Error('polyfill failed because global object is unavailable in this environment');
}
}
var P = local.Promise;
if (P) {
var promiseToString = null;
try {
promiseToString = Object.prototype.toString.call(P.resolve());
} catch (e) {
// silently ignored
}
if (promiseToString === '[object Promise]' && !P.cast) {
return;
}
}
local.Promise = Promise$2;
}
// Strange compat..
Promise$2.polyfill = polyfill;
Promise$2.Promise = Promise$2;
Promise$2.polyfill();
return Promise$2;
})));
//# sourceMappingURL=es6-promise.auto.map