Question

我有一些来自数据库的平面数据，如下所示：

List<FlatDataGroup> elements = new List<FlatDataGroup>()
        {
            new FlatDataGroup {Text = "", GroupID = 1, ParentGroupID = 0, GroupName = "Admin", UserID = 1, UserName = "John Doe"},
            new FlatDataGroup {Text = "", GroupID = 1, ParentGroupID = 0, GroupName = "Admin", UserID = 2, UserName = "Jane Smith"},
            new FlatDataGroup {Text = "", GroupID = 2, ParentGroupID = 1, GroupName = "Support", UserID = 3, UserName = "Johnny Support"},
            new FlatDataGroup {Text = "", GroupID = 3, ParentGroupID = 2, GroupName = "SubSupport", UserID = 4, UserName = "Sub Johnny Support"},
            new FlatDataGroup {Text = "", GroupID = 4, ParentGroupID = 1, GroupName = "Production", UserID = 5, UserName = "Johnny Production"}
        };

我想将其转换为：

List<Group> model = new List<Group>
            {
                new Group()
                {
                    ID = 1,
                    Name = "Admin",
                    ParentGroupID = 0,
                    Type = "Group",
                    Users = new List<User>()
                    {
                        new User()
                        {
                            ID = 1,
                            Name = "John Doe",
                            GroupID = 1,
                            Type = "User",
                        },
                        new User()
                        {
                            ID = 2,
                            Name = "Jane Smith",
                            GroupID = 1,
                            Type = "User",
                        },
                    },
                    Groups = new List<Group>
                    {
                        new Group()
                        {
                            ID = 2,
                            Name = "Support",
                            ParentGroupID = 1,
                            Type = "Group",
                            Users = new List<User>()
                            {
                                new User()
                                {
                                    ID = 3,
                                    Name = "Johnny Support",
                                    GroupID = 2,
                                    Type = "User",
                                }
                            },
                            Groups = new List<Group>()
                            {
                                new Group()
                                {
                                    ID = 3,
                                    Name = "SubSupport",
                                    ParentGroupID = 2,
                                    Type = "Group",
                                    Users = new List<User>()
                                    {
                                        new User()
                                        {
                                            ID = 4,
                                            Name = "Sub Johnny Support",
                                            GroupID = 3,
                                            Type = "User",
                                        }
                                    },
                                    Groups = null
                                }
                            }
                        },
                        new Group()
                        {
                            ID = 4,
                            Name = "Production",
                            ParentGroupID = 1,
                            Type = "Group",
                            Users = new List<User>()
                            {
                                new User()
                                {
                                    ID = 5,
                                    Name = "Johnny Production",
                                    GroupID = 4,
                                    Type = "User",
                                }
                            },
                            Groups = null
                        }
                    }
                }
            };

最终将在树视图中显示如下：

+ Admin（Group）
John Doe（用户）
简史密斯（用户）
+支持（组）
约翰尼支持（用户）
+ SubSupport（Group）
Sub Johnny支持（用户）
+生产（集团）
约翰尼制作（用户）

到目前为止，我已经提出将平面数据转换为上述模型：

List<Group> model = new List<Group>();

        var parentGrouping = elements.GroupBy(x => x.ParentGroupID);

        foreach (var parentGroup in parentGrouping)
        {
            var grouping = parentGroup.GroupBy(y => y.GroupID);

            foreach (var group in grouping)
            {
                Group groupItem = new Group()
                {
                    ID = group.FirstOrDefault().GroupID,
                    Name = group.FirstOrDefault().GroupName,
                    ParentGroupID = group.FirstOrDefault().ParentGroupID,
                    Type = "Group",
                    Users = new List<User>()
                };

                foreach (var user in group)
                {
                    groupItem.Users.Add(new User()
                        {
                            ID = user.UserID,
                            Name = user.UserName,
                            GroupID = user.GroupID,
                            Type = "User",
                        });
                }

                model.Add(groupItem);
            }
        }

我的所有小组都与他们的子级用户一起出现，但不保留层次结构。我想我可能需要递归地做这件事，但我似乎无法理解它。任何帮助将不胜感激。

为了完整起见，以下是模型：

public class FlatDataGroup
{
    public string Text { get; set; }
    public int GroupID { get; set; }
    public int ParentGroupID { get; set; }
    public string GroupName { get; set; }
    public int UserID { get; set; }
    public string UserName { get; set; }
}

public class Group
{
    public int ID { get; set; }
    public int ParentGroupID { get; set; }
    public string Name { get; set; }
    public List<Group> Groups { get; set; }
    public List<User> Users { get; set; }
    public string Type { get; set; }
}

public class User
{
    public int ID { get; set; }
    public int GroupID { get; set; }
    public string Name { get; set; }
    public string Type { get; set; }
 }

Answer 1

我在3次通过中做到了这一点：

创建所有Group类，并使用除子组之外的数据填充它们，将它们逐步添加到字典映射ID到组。

遍历字典中的所有组并将子项添加到其父项中。 Groups孩子名单。

返回没有父组的所有组的筛选列表 - 这些是根组。（我还按ID对它们进行排序，以删除字典将引入的随机排序。）

因此：

public static class FlatDataGroupExtensions { public const string UserType = "User"; public const string GroupType = "Group"; public static List<Group> ToGroups(this IEnumerable<FlatDataGroup> elements) { // Allocate all groups and index by ID. var groups = new Dictionary<int, Group>(); foreach (var element in elements) { Group group; if (!groups.TryGetValue(element.GroupID, out group)) groups[element.GroupID] = (group = new Group() { ID = element.GroupID, Name = element.GroupName, ParentGroupID = element.ParentGroupID, Type = GroupType }); group.Users.Add(new User() { GroupID = element.GroupID, ID = element.UserID, Name = element.UserName, Type = UserType }); } // Attach child groups to their parents. foreach (var group in groups.Values) { Group parent; if (groups.TryGetValue(group.ParentGroupID, out parent) && parent != group) // Second check for safety. parent.Groups.Add(group); } // Return only root groups, sorted by ID. return groups.Values.Where(g => !groups.ContainsKey(g.ParentGroupID)).OrderBy(g => g.ID).ToList(); } }

我还修改了你的Group课程以自动分配列表：

public class Group { List<Group> groups = new List<Group>(); List<User> users = new List<User>(); public int ID { get; set; } public int ParentGroupID { get; set; } public string Name { get; set; } public string Type { get; set; } public List<Group> Groups { get { return groups; } } public List<User> Users { get { return users; } } public override string ToString() { return string.Format("Group: ID={0}, Name={1}, Parent ID={2}, #Users={3}, #Groups={4}", ID, Name, ParentGroupID, Users.Count, Groups.Count); } }

平面数据到层次模型C＃

1 个答案: