声明并将集合用作属性 [英] Declaring and using a collection as a Property

问题描述

好的 - 我已经阅读并且我已经玩过了，我一直空白，主题几乎到达那里但是没有



我的两个我的VB2010学习项目中的课程是：项目和目标



两者都存储在相关数据表中，其中每个目标都有一个Project_ID（一对一）许多关系）



我想将Objectives集合作为Projects类的属性。我想我会使用myProject.PopulateObjectives方法填充

OK - I've read and I've played around and I keep coming up blank with topics that almost get there but don't

Two of my classes in my VB2010 learning project are: "Project" and "Objective"

Both are stored in related data tables where each Objective has a Project_ID (a one-to-many relationship)

I want to incorporate an "Objectives" collection as a Property of the Projects class. I'm thinking I would populate that with a myProject.PopulateObjectives method calling

Select* from Objectives WHERE Project_ID=[@Project_ID]

和这将允许我随后对该项目（和其他项目）进行大量计算和迭代



如何为此声明属性和方法？



感谢所有帮助

and that would allow me then to do a number of calculations and iterations with that project (and other projects)

How do I declare the Property and Methods for this?

All help gratefully received

推荐答案

有太多事情要解释......只有一个建议：使用数据访问层从数据库返回数据;）

看看这里：

教程1：创建数据访问层 [ ^ ]

数据访问层（第一部分） [ ^ ]

VB.Net中的通用数据访问层 [ ^ ]

There is too many things to explain... Only one suggestion: use Data Access Layer to return data from database ;)
Have a look here:
Tutorial 1: Creating a Data Access Layer[^]
Data Access Layer (Part I)[^]
A Generic Data Access Layer in VB.Net[^]

我在这里缺少的是我需要a）声明一个名为Objectives as的属性目标b）的集合/列表设置调用以填充目标和c）使用仅限于该项目ID的查询设置子拓扑目标



数据Maciej提出的图层教程非常有用



有时候人们不知道他们不知道什么

What I was missing here was that I needed to a) declare a property called Objectives as a collection/list of Objective b) set up a call to populate the objectives and c) set up a sub topopulate objectives using a query restricted to that projectID

The data layer tutorial proposed by Maciej was very useful

Sometimes people don't know what they don't know

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