Question

情况就是这样：

$scope.signupNow = function () {
  retrieveData();
  console.log($scope.userid);
}

function retrieveData(){
    // ** some http request **
    $scope.userid = id; 
}

现在http请求需要一些时间来执行，“$ scope.userid”中没有值，因为它只是在调用函数后打印。

你能否建议如何等待回应????

Answer 1

$scope.signupNow = function () {

  retrieveData().then(funtion(response) {
    console.log(response.data);
    // do here what you need
  });
}

function retrieveData(){
  return $http.get('url');
}

Answer 2

好的，如果你想等到http响应，那么你可以使用回调函数

$scope.signupNow = function () {

    retrieveData(function(){

        console.log($scope.userid);
    });   
}

function retrieveData(callback){
    // ** some http request **
    $scope.userid = id; 
    callback();
}

Answer 3

使用angularJs promise -

$scope.signupNow = function () {
   var promise  = retrieveData();
   promise.then(function(success) {
     console.log($scope.userid);
   }, function(reason) {
     alert('Failed: ' + reason);
   });

 }


function retrieveData(){
 var deferred = $q.defer();
 (your http request).then(){
   $scope.userid = id;
   deferred.resolve('success');
  }
  return deferred .promise;
}

如何等待响应来自$ http请求并在angularjs中的$ scope变量中赋值？

3 个答案: