首页 > 代码库 > [Angular-Scaled Web] 9. Control your promises with $q
[Angular-Scaled Web] 9. Control your promises with $q
Learn how to manually control how asynchronous requests are handled with the use of promises. Because $http is built to work with promises, we saw a foreshadow of them in the previous lesson. We will take this a step further but seeing how to manually create a promise and then resolve or reject it as we see fit.
angular.module(‘eggly.models.categories‘, []) .service(‘CategoriesModel‘, function ($http, $q) { var CategoriesModel = {}, URLS = { FETCH: ‘data/categories.json‘ }, categories; function extract(result) { return result.data; } function cacheCategories(result) { categories = extract(result); return categories; } CategoriesModel.getCategories = function() { return (categories) ? $q.when(categories) : $http.get(URLS.FETCH).then(cacheCategories); }; CategoriesModel.getCategoryByName = function(categoryName) { function findCategory(){ return _.find(categories, function(c){ return c.name == categoryName; }) } return $q(function(resolve, reject) { //resolve it when categories are set if(categories){ resolve(findCategory()); }else{ //if not set, get the categories CategoriesModel.getCategories() .then(function() { resolve(findCategory()); }) } }) }; return CategoriesModel; });
[Angular-Scaled Web] 9. Control your promises with $q
声明：以上内容来自用户投稿及互联网公开渠道收集整理发布，本网站不拥有所有权，未作人工编辑处理，也不承担相关法律责任，若内容有误或涉及侵权可进行投诉： 投诉/举报 工作人员会在5个工作日内联系你，一经查实，本站将立刻删除涉嫌侵权内容。