Question

有人可以解释为什么$ scope.shopLocation在运行for循环后不会更改为= special。我需要在控制器中进一步访问这个var数据，我无法在http.get中访问它

如果有任何人有关于范围/变量等的良好解释的链接，我将不胜感激。

.controller('MapCtrl', function($scope, $http) {    
    $scope.shopLocation = [];

    $http.get('/x/xx/xxx/advertsearch_json.php')
        .then(function(res) {
            $scope.jobs1 = res.data;

            var special = [];

            var categories = [];

            for ( var i=0; i < $scope.jobs1.length; i++ )
                categories[$scope.jobs1[i]['CHCO_LOCATION']] = $scope.jobs1[i];

            $scope.jobs1 = new Array();

            for ( var key in categories )
                special.push(categories[key]);

            $scope.shopLocation = special;
        });
    })

Answer 1

我认为问题在于，您不能确保只有在异步操作完成后才会发生其余逻辑。您需要做的是在return调用的then函数中http所需的信息，然后使用对promise的引用以获取返回的值。它的工作原理如下：

var myPromise = $http.get('whatever').then(function(resp) {
  // do what you need to do
  return something; // return the value you'll need later
});

// elsewhere

$scope.foo = function() {    
  myPromise.then(function(something) {
    // use the value you returned ^. the logic here will run when the value is definitely available.
  });
};

这样，如果你调用$scope.foo，你的逻辑肯定会得到异步操作的值。与以下代码对比：

$scope.something;

$http.get('whatever').then(function(resp) {
  $scope.something = //whatever
});

$scope.foo = function() {    
  console.log($scope.something); // no guarantee this will be set
};

Answer 2

我相信你的异步代码导致更新发生在摘要周期之外。因此，值正在被更改，但您没有看到它反映在屏幕上。

在这种情况下，您需要应用范围 - 所以在$scope.shopLocation = special;添加：

之后

$scope.$apply();

Answer 3

我认为这与特殊范围有关。它在http.get结束后被破坏了。您实际上并未复制所提供代码中的内容。你应该做一个深刻的副本。 https://docs.angularjs.org/api/ng/function/angular.copy

.controller('MapCtrl', function($scope, $http) {    
$scope.shopLocation = [];

$http.get('/x/xx/xxx/advertsearch_json.php')
    .then(function(res) {
        $scope.jobs1 = res.data;

        var special = [];

        var categories = [];

        for ( var i=0; i < $scope.jobs1.length; i++ )
            categories[$scope.jobs1[i]['CHCO_LOCATION']] = $scope.jobs1[i];

        $scope.jobs1 = new Array();

        for ( var key in categories )
            special.push(categories[key]);

        $scope.shopLocation = angular.copy(special);
    });
})

Answer 4

所以这就像调用后来使用＆＃39;然后＆＃39;

中的新数据的函数一样简单

    $http.get('/pb3/corporate/Apostrophe/advertsearch_json.php')
        .then(function(res) {
            $scope.jobs1 = res.data;

            var special = [];

            var categories = [];

            for ( var i=0; i < $scope.jobs1.length; i++ )
                    categories[$scope.jobs1[i]['CHCO_LOCATION']] = $scope.jobs1[i];
                    $scope.jobs1 = new Array();
            for ( var key in categories )
                    special.push(categories[key]);


            $scope.shopLocation = special;

            **createPoints();**

    });

感谢大家的帮助

从http.get更新$ scope var

4 个答案: