Currency 货币 filter

   <div ng-controller="ctrl">
        <div>{{ 100 | myCurrency}}</div>
        <div ng-click="change1(‘SGD‘)">change</div>         
    </div>   

               angular.module("Main", dependentModuleList).
                    controller("ctrl", function ($scope, currencyService) {
                        $scope.change1 = function (code) {
                            currencyService.changeCodeTo(code);
                        };
                    });  

  angular.module("Currency", []).
        provider("currencyService", [function () {
            var that = this;
            this.defaultCode = "USD"; //允许通过provider修改
            this.$get = ["$rootScope", function ($rootScope) {
                var COOKIE_KEY = "currecyCode";
                var SERVICE_PATH = "//service.stooges.com.my/currency.ashx?defaultCode=" + that.defaultCode; //这里可以请求一个当前的 rate table (来自 http://www.xe.com/currencytables)
                var defaultCode = that.defaultCode;
                var currentCode = G.s.Cookie.get(COOKIE_KEY) || defaultCode;
                var rateColletion = {}; //{USD:3.1538542348}
                var ajaxing = false;

                function getRateFromServer() {                  
                    ajaxing = true;
                    G.s.fn.jsonp(SERVICE_PATH).then(function (response) {                       
                        ajaxing = false;
                        rateColletion = JSON.parse(response).data;                        
                        $rootScope.$digest(); //手动渲染                    
                    }, function () {
                        console.log("get currency rate table fail !");
                    });
                }
                function getMoneyFormat(money, code) {
                    return code + " " + (parseFloat(money).toFixed(2));
                }
                return {
                    changeCodeTo: function (code) {                        
                        currentCode = code; //请在外部digest
                        G.s.Cookie.set(COOKIE_KEY, currentCode, new Date().addMonths(1));                        
                    },
                    convertMoney: function (money) {                     
                        if (defaultCode === currentCode || ajaxing) {  //正在向服务器请求的话也直接返回                       
                            return getMoneyFormat(money, currentCode); 
                        }                      
                        var rate = rateColletion[currentCode];
                        if (rate != undefined) {                           
                            return getMoneyFormat(money / rate, currentCode); //这里是用除法
                        }
                        else {                          
                            getRateFromServer(); //第一次得向服务器请求rate表格
                            return getMoneyFormat(money, currentCode);
                        }
                    }
                }
            }]
        }]).
        filter("myCurrency", ["$rootScope", "currencyService", function ($rootScope, currencyService) {
            //手动调用的话要注意, 如果没有rate,会直接返回原value
            return function (money) {                
                return currencyService.convertMoney(money);
            }
        }]);