.then没有定义？

Question

I'm getting this error, when trying to get response from my service, in which i have placed my Ajax call! I want the controller code to delay that is why i am returning a promise from service. But I am getting .then of undefined error.
Here is the code

app.service('abc', function(){

    var function() {

        return $http({method : "POST",
                            url :"url",
                            data:{
                                a}
        }).then(function mySuccess(response) {        
                 return response;
        })
    }
});    

in controller

var promise=servicename.functionname();

promise.then(res)
{} 

.then of undefined is the error I am getting. Any solution?

Answer 1

Update service and inject $http

app.service('abc', function ($http) {
    this.functionName = function (data) {
        return $http({
            method: "POST",
            url: "url",
            data: data
        }).then(function mySuccess(response) {
            return response.data;
        })
    };
});

Controller

app.controller('myController', function (abc) {
    abc.functionName({
        a: 'a'
    }).then((data) => console.log(data))
});

Answer 2

Here the code will not wait the return inside then() and it will execute the code ahead. And as it does no find any return statement it will return undefined. To fix this in the service function you will return just the promise so your return statement will look something like this

return $http({
           method : "POST",
           url :"url",
           data:{a}
   })

The controller code will be same