Question

我无法将以下Lodash语句转换为在我在工作中继承并尝试修复错误的应用程序中工作的内容。目前，我们的系统中只有一个设备出现问题当两个设备具有相同的名称并且以下代码似乎是罪魁祸首时返回，因为它只会返回第一个＆＃34; true＆＃34;数组中的值：

var group = _.find(groupList, {id: id});

我如何成功地将其转换为迭代数组中所有对象然后返回这些对象的语句？我尝试了以下选项无济于事：

 var group = _.filter(groupList, {id: id});

和

 var group = _.every(groupList, {id: id});

和

 var group = _.forEach(groupList, {id: id}) 
 return {id};

我知道我的语法中可能遗漏了一些东西。任何帮助将非常感激。运行Lodash v3.7.0

这是指令中的其余代码，以防有人感兴趣或看到我可能遗失的其他内容：

define(['./../_module'], function (directives) {
'use strict';
directives.directive('dmGroupedList', ['$compile', '$state', 'APP_CONSTANTS', function ($compile, $state, APP_CONSTANTS) {
    return {
        restrict: 'A',
        scope: {
            items: '=',
            groupBy: '=',
            actions: '=',
            nonameGroupLabel: '='
        },
        templateUrl: function (elem, attrs) {
            return attrs.templateUrl || 'views/shared-templates/grouped-list.html';
        },
        link: function (scope, element, attrs) {
            scope.$watchGroup(['items', 'groupBy', 'nonameGroupLabel'], function () {
                scope.groupList = [];
                scope.groupedItems = {};

                var actions = scope.actions[scope.groupBy];

                _.forEach(scope.items, function (item) {
                    scope.handlers.getGroups(scope.groupList, item, scope.items, scope.groupBy, actions);
                });

                _.forEach(scope.groupList, function (group) {
                    var items = scope.groupedItems[group.id];
                    items = _.sortBy(items, function (item) {
                        return item.description;
                    });

                    scope.groupedItems[group.id] = items;
                });

                var groupsToSort = _.where(scope.groupList, {unassigned: false});
                var unassignedGroups = _.sortBy(_.where(scope.groupList, {unassigned: true}), 'name');
                scope.groupList = _.sortBy(groupsToSort, function (group) {
                    return group.name;
                });
                //adds unassigned groups to a new array via the javascript "push" method
                if (angular.isDefined(unassignedGroups)) {
                    for (var i = 0; i < unassignedGroups.length; i++) {
                        scope.groupList.push(unassignedGroups[i]);
                    }
                }
            });

            scope.handlers = {
                getGroups: function (groupList, item, items, groupBy, actions) {
                    var group = item[groupBy];

                    if (_.isEmpty(group)) {
                        scope.handlers.addGroupToList(groupList, APP_CONSTANTS.DEVICE_NONE_NAME_MAPPING.NONE, items, groupBy, item, actions, scope);
                    }
                    else {
                        if (angular.isArray(group) || angular.isObject(group)) {
                            _.forEach(group, function (groupName) {
                                if (groupName == APP_CONSTANTS.ZERO) {
                                    scope.handlers.addGroupToList(groupList, APP_CONSTANTS.DEVICE_NONE_NAME_MAPPING.NONE, items, groupBy, item, actions, scope);
                                    return;
                                }

                                scope.handlers.addGroupToList(groupList, groupName, items, groupBy, item, actions, scope);
                            })
                        } else {
                            scope.handlers.addGroupToList(groupList, group, items, groupBy, item, actions, scope);
                        }
                    }
                },
                addGroupToList: function (groupList, groupId, items, groupBy, item, handlers, scope) {
                    var id = _.camelCase(groupId);

                   var group = _.find(groupList, {id: id});
                    //var group = _.forEach(groupList, {id: id})
                    //return {id};

                    if (!group) {
                        var name = '';
                        var unassigned = false;
                        var link = null;

                        if (groupId == APP_CONSTANTS.DEVICE_NONE_NAME_MAPPING.NONE || groupId == APP_CONSTANTS.DEVICE_NONE_NAME_MAPPING.NONE_PARENT_ID) {
                            if (groupId == APP_CONSTANTS.DEVICE_NONE_NAME_MAPPING.NONE_PARENT_ID) {
                                name = APP_CONSTANTS.DEVICE_NONE_NAME_MAPPING.NONE;
                            } else {
                                name = APP_CONSTANTS.DEVICE_NONE_NAME_MAPPING.UNASSIGNED;
                            }

                            unassigned = true;
                        } else {
                            link = handlers.getGroupLink(groupId);
                            name = handlers.getGroupName(groupId, items);
                        }

                        group = {id: id, name: name, unassigned: unassigned, link: link};

                        groupList.push(group);
                    }

                    scope.groupedItems[group.id] = scope.groupedItems[group.id] || [];

                    if (angular.isDefined(handlers.processingGroup)) {
                        handlers.processingGroup(group, groupList, groupId, items, groupBy, item, handlers, scope);
                    } else {
                        scope.groupedItems[group.id].push({
                            description: handlers.getItemDescription(item),
                            link: handlers.getItemLink(item)
                        })
                    }
                }
            };
        }
    };
}]);

}）;

Answer 1

您可以使用filter：

var group = groupList.filter((group) => group.id === id);

编辑：只返回一个元素，而不是一个数组，当只有一个匹配时，你可以执行以下操作：

var checkSingle = (groups) => groups.length === 1 ? groups[0] : groups;
var group = checkSingle(groupList.filter((group) => group.id === id));

Answer 2

您可以_(groupList).groupBy('id').get(id)：

＆＃13;

var groupList = [
  { id: 1, name: 'site' },
  { id: 2, name: 'test' },
  { id: 2, name: 'prod' },
  { id: 3, name: 'dev' },
  { id: 4, name: 'back' },
  { id: 4, name: 'front' },
  { id: 5, name: 'sprint' }
];

console.log(_(groupList).groupBy('id').get(2));
console.log(_(groupList).groupBy('id').get(3));
console.log(_(groupList).groupBy('id').get(4));

＆＃13;

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.min.js"></script>

＆＃13;

Lodash / JS - 将_.find语句转换为_.forEach

2 个答案: