How to wait function call return value before go to the next line in angular js

Question

I have two functions is_exist() and save() functions. In save function I calls is_exist() function before performing a save.it return boolean value. but my problem is save() function is not wait until is_exist() function to return the value.after is_exist() function called it just jump into next line and continue execute bellow lines, after save() finished is_exist() function return the value

var app = angular.module('my_app', [])
app.controller('my_con', ['$scope', '$http', function($scope, $http) {

    $scope.save = function(sector) {
        var del_status = $scope.is_exist(sector);

        console.log(del_status); // is_exsis return value

        if(!del_status) {
            // save
        }
    }

    $scope.is_exist = function(sector) {
        $http({
            method : 'POST',
            url : '/is_data_exist',
            contentType : 'application/json; charset=utf-8',
            data : angular.toJson({
                'sector': sector
            }),
            dataType: 'json',
        }).then(function successCallback(response) {

            console.log(response.data); //http respond

            if(response.data == 'False') {
                return false;
            }
            else {
                return true;
            }
        })
    }
}])

is there any way to wait until is_exsis() function to return value and then go to next line

it is asynchronous, it means you "can't", because you don't know when the promise will be resolved. What you can do is pass the following code as a function to your promise, so that the promise executes it. something like `var del_status = $scope.is_exist(sector, function(){ console.log(del_status); /* etc */ });` (be careful, you have a typo, exist != exsis) — Kaddath, Jun 12 '17 at 11:45
duplicate : https://stackoverflow.com/questions/14220321/how-do-i-return-the-response-from-an-asynchronous-call?rq=1 — Nevosis, Jun 12 '17 at 12:05
@Nevosis [link](https://stackoverflow.com/questions/14220321/how-do-i-return-the-response-from-an-asynchronous-call?rq=1) your link is about ajax and my question is about angularjs — user6900333, Jun 12 '17 at 12:14
My link and your question is about asynchronous call in javascript. It is the exact same thing in angular, react, ajax, jquery, nodejs, etc... How to handle async call in js ? Mainly promises and callbacks. — Nevosis, Jun 12 '17 at 12:16

score 1 · Answer 1 · answered Jun 12 '17 at 11:45

Use callback function in $scope.is_exsis(sector); and perform this action inside callback function -

 var del_status = $scope.is_exsis(function(data){
    console.log(del_status); // is_exsis return value

    if(!del_status) {
        // save
    }
 });

score 0 · Answer 2 · edited Jun 12 '17 at 12:26

You should be able to return the Promise and then chain it so that the save isn't completed until is_exists is done.

$scope.save = function(sector) {
    $scope.is_exsis(sector).then(function(del_status){

        console.log(del_status); // is_exsis return value

        if(!del_status) {
        // save
        }
   });

}

$scope.is_exist = function(sector) {
    return $http({
        method : 'POST',
        url : '/is_data_exist',
        contentType : 'application/json; charset=utf-8',
        data : angular.toJson({
            'sector': sector
        }),
        dataType: 'json',
    }).then(function successCallback(response) {

        console.log(response.data); //http respond

        if(response.data == 'False') {
            return false;
        }
        else {
            return true;
        }
    })
}

How to wait function call return value before go to the next line in angular js

2 Answers2