javascript - 来自 ng-model 的 Controller 中的未定义参数

Question

我从 API 获得了数据，我用它来显示表单。表单包含级联选择字段。我有 2 个函数可以根据下一次选择的结果过滤我的数组，但我无法从 ng-model 中读取属性。

例如，我选择第一个选项并获取它的 ID，然后我需要将该 ID 传递给我在 Controller 中的函数，它可以过滤数组以返回正确的选项。

API 数据

section: { id: "111", name: "Section1" }
nomination: { id: "666", name: "Nomination2" }
category: { id: "999", name: "Category2"}

服务

const allSections = [
    { id: '111', section: 'Section1' },
    { id: '222', section: 'Section2' },
    { id: '333', section: 'Section3' },
];
const allNominations = [
    { id: '555', sectionId: '111', nomination: 'Nomination1' },
    { id: '666', sectionId: '222', nomination: 'Nomination2' },
    { id: '777', sectionId: '333', nomination: 'Nomination3' },
];
const allCategories = [
   { id: '999', sectionId: '111', category: 'Category1' },
   { id: '888', sectionId: '222', category: 'Category2' },
   { id: '000', sectionId: '333', category: 'Category3' },
];
getSection() {
   return allSections;
},
getSectionNomination(sectionId) {
   const nominations = ($filter('filter')(allNominations, { sectionId }));
   return nominations;
},
getNominationCategory(sectionId) {
   const categories = ($filter('filter')(allCategories, { sectionId }));
   return categories;
},

Controller

$scope.award = {};
$scope.sections = awards_service.getSection();
$scope.getSectionNominations = () => {
    $scope.nominations = 
    awards_service.getSectionNomination($scope.award.section.id);
    $scope.categories = [];
};
$scope.getNominationCategories = () => {
    $scope.categories = 
    awards_service.getNominationCategory($scope.award.section.id);
};

查看

<select ng-model="award.section.id"
        ng-change="getSectionNominations()" 
        ng-options="object.id as object.section for object in sections")
</select>

<select ng-model="award.nomination.id"
        ng-change="getNominationCategories()"
        ng-options="object.id as object.section for object in nominations") 
</select>

<select ng-model="award.category.id"
        ng-options="object.id as object.section for object in categories"
</select>

我尝试从 API 数据中获取选定的 ID 并过滤我的数组。在 View 中，我可以看到正确的 ID 作为 award.section.id，但是当我将此 papameter 传递到我的 Controller 中时，我得到未定义的结果。$scope.award.section.id 未定义。

Answer 1

尝试将 select 的当前值传递给函数:

$scope.sectionId = 0;
if ($scope.sections && $scope.sections[0]) {
  $scope.sectionId = $scope.sections[0].id;
}
$scope.getSectionNominations = (sectionId) => {
    if (!sectionId) return;

    $scope.nominations = awards_service.getSectionNomination(sectionId);
    $scope.categories = [];
};

在 html 中:

<select 
  ng-model="sectionId"
  ng-change="getSectionNominations(sectionId)" 
  ng-options="object.id as object.section for object in sections"
>
</select>

查看答案 here在将变量作为参数传递