如何将关系数据集转换为嵌套的ObservableCollection？ [英] How would I convert a relational dataset to a nested ObservableCollection?

问题描述

我现在卡住了。我有一个包含2个相关表的数据集。它是一个简单的父表，带有一个相关的子表。



由于各种原因，我需要将数据集转换为嵌套的ObservableCollection。以下Linq代码适用于1个问题：我在嵌套集合中缺少where子句，因此所有子节点都是父节点的一部分是不正确的。

I''m stuck at the moment. I have a dataset with 2 related tables. It''s a simple parent table with a single related child table.

For various reasons, I need to convert the dataset into a nested ObservableCollection. The following Linq code works with 1 issue: I''m missing a where clause on the nested collection so all of the children are part of the parent which is incorrect.

this.ocApps = new ObservableCollection<Models.ApplicationTypesModel>(this.dsApps.tAppTypes.AsEnumerable().Select(apptype => new Models.ApplicationTypesModel
                {
                    AppType = apptype.nvarAppType,
                    Apps=new ObservableCollection<Models.ApplicationModel>(this.dsApps.tApps.AsEnumerable().Select(apps=>new Models.ApplicationModel
                    {
                        idAppId=apps.idAppId,
                        strAppName=apps.nvarAppName,
                        strEnvironment=apps.nvarEnvironment,
                        strAppType=apps.nvarAppType,
                        dtLastPrivACCertDate= apps.dtLastPrivACCertDt
                    }).where(the parent table.apptype value = the child table.apptype value))
                }));

我想我需要在内部选择的位置，这是有道理的...但我不知道在哪里或如何把它放在哪里。







有没有人有一些建议？



谢谢

I think I need a where on the inner select, which makes sense...but I''m not sure where or how to put the where.



Does anyone have some suggestions?

Thanks

推荐答案

这完美无缺。 where的语法是我所缺少的。以下URL可能对需要将关系数据集转换为嵌套ObservableCollection的其他人有所帮助。我的意图是使用这个特定应用程序的MVVM模式的ViewModel。



http://stackoverflow.com/questions/6359980/proper-linq-where-clauses



格式}）。其中（app => app.strAppType == apptype.nvarAppType）是扔我的东西。

This works perfectly. The syntax of the "where" is what I was missing. The following URL may be of help to someone else who needs to convert a relational dataset to a nested ObservableCollection. My intent is in the ViewModel of a MVVM pattern with this particular app.

http://stackoverflow.com/questions/6359980/proper-linq-where-clauses

The format of "}).Where(app=>app.strAppType==apptype.nvarAppType)" is what was throwing me.

this.ocApps = new System.Collections.ObjectModel.ObservableCollection<Models.ApplicationTypesModel>(this.dsApps.tAppTypes.AsEnumerable().Select(apptype => new Models.ApplicationTypesModel
                {
                    AppType = apptype.nvarAppType,
                    Apps = new System.Collections.ObjectModel.ObservableCollection<Models.ApplicationModel>(this.dsApps.tApps.AsEnumerable().Select(apps => new Models.ApplicationModel
                    {
                        idAppId = apps.idAppId,
                        strAppName = apps.nvarAppName,
                        strEnvironment = apps.nvarEnvironment,
                        strAppType = apps.nvarAppType,
                        dtLastPrivACCertDate = apps.dtLastPrivACCertDt
                    }).Where(app=>app.strAppType==apptype.nvarAppType))
                }));

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