從服務返回$ http時拒絕承諾

Question

我知道我可以這樣做：

angular.module('app.services').service('Resources', function ($q) {
  this.ProductData = function() {
    var deferred = $q.defer();

    $http.get(url)
        .then(function(result) {
            deferred.resolve(result);
        }, function() {
            defered.reject("error");
        });

    return deferred.promise;
  }
});

但是我可以避免創建延遲的obj，但仍然能夠解析和拒絕嗎？

angular.module('app.services').service('Resources', function () {
  this.ProductData = function() {

    return $http.get(url)
        .then(function (result) {
            // how would I do 'deferred.resolve or deferred.reject' here?
        }, function () {
            // how would I do 'deferred.reject' here?
        });
  }
});

Answer 1

您應該避免為$http創建deferred承諾和另一個保證。

如果在實際的$http調用成功后需要拒絕承諾，則需要返回$q.reject() ：

return $http.get(url)
    .then(function(result){
       if (result.data.length === 0) return $q.reject("error");

       return result;
    }