可以_lodash测试一个数组来检查数组元素是否有一个具有特定值的字段？ [英] Can _lodash test an array to check if an array element has a field with a certain value?

问题描述

我有一个变量 selectedSubTopicId ，我有一个subTopic对象数组： objectiveDetail.subTopics [] 。每个 subTopic 对象都有字段 subTopicId

I have a variable selectedSubTopicId and I have an array of subTopic objects: objectiveDetail.subTopics[]. Each subTopic object has a field subTopicId

我想用它来启用或禁用和添加主题按钮。我是否可以在ng-disabled中使用lodash来测试此数组，并且如果数组的任何 subTopic 对象元素具有 subTopicId 等于 selectedSubTopicId 。

I would like to use this to enable or disable and Add topic button. Can I use lodash in the ng-disabled to test this array and report true if any subTopic object element of the array has a subTopicId that is equal to the selectedSubTopicId.

这是objectiveDetail中的数据样本。在这种情况下，subTopics数组中只有一个元素。

Here's a sample of the data that's in objectiveDetail. In this case there's just one element in the subTopics array.

{"objectiveDetailId":285,
 "objectiveId":29,
 "number":1,
 "text":"x",
 "subTopics":[{"subTopicId":1,
               "number":1}]
}

这是我的角色控制器中由thefourtheye建议的代码：

Here is the code in my Angular Controller suggested by thefourtheye:

    $scope.checkDuplicateSubTopicId = function (objectiveDetail, sSubTopic) {
        if (_.some(objectiveDetail.subTopics, function(currentTopic) {
            return _.contains(currentTopic, selectedSubTopicId);
        })) {
            return true;
        } else {
            return false;
        }
    }

点击功能未显示的我的按钮看起来像这样：

My button with the click function not shown looks like this:

   <button data-ng-disabled="checkDuplicateSubTopicId(objectiveDetail, subTopicId)">
       Add Topic
   </button>

问题是它不能正常工作且按钮没有显示已禁用。

The problem is that it's not quite working and the button does not show disabled.

推荐答案

_{你没有要求怎么做，但我认为那是你想知道的。}

正如我已经提到的，你可以使用 _。some ，它将迭代数组中的每个元素并执行回调。在该回调中，您可以测试主题​​属性的值是否等于变量的值：

As I already mentioned, you can use _.some, which will iterate over every element in the array and execute a callback. In that callback you can test whether the value of the topic's property equals the value of the variable:

var result = _.some(objectiveDetail.subTopics, function (topic) {
  return topic.subTopicId === selectedSubTopicId;
});

_。some 将跳过剩余的元素如果它找到了一个回调返回的 true 。

_.some will skip the remaining elements if it found one for which the callback returned true.

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