列表（人）订单 [英] List(Of Person) ORDER

问题描述

请看下面的代码：

Public Class PersonTest

    Public Function ListTest()
        Dim list As List(Of Person) = New List(Of Person)
        Dim p1 As Person = New Person(1, "Ian")
        Dim p2 As Person = New Person(2, "Steven")
        Dim p3 As Person = New Person(3, "Sharon")
        list.Add(p1)
        list.Add(p2)
        list.Add(p3)
        For Each p As Person In list
            MsgBox(p.IDNumber)
        Next

    End Function

End Class

Public Class Person
    Public IDNumber As Integer
    Public Name As String

    Public Sub New(ByVal id As Integer, ByVal name As String)
        IDNumber = id
        name = name
    End Sub

End Class

Public Class Form1

    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        Dim pt As PersonTest = New PersonTest
        pt.ListTest()
    End Sub
End Class

我希望消息框打印：1,2,3它是做什么的。您可以确认列表使用插入订单。我计划将数据库查询的结果存储在列表中：

I expect the Message Box to print: 1,2,3 which it does. Can you confirm that List uses insertion order. I am planning to store the results of database queries in a list i.e:

SELECT * FROM Person ORDER BY ID

SELECT * FROM Person ORDER BY ID

SQL语句按ID排序。我可以假设列表也会按照ID进行排序吗？

The SQL statement is ordered by ID. Can I assume that the List will also be ordered by ID?

我问的原因是因为我的问题的答复者在这里：数据访问层返回DataTable ，建议使用列表从数据访问层返回对象。

The reason I ask is because the answerer to my question here: Data Access Layer returns DataTable, suggests using a List to return an object from a Data Access Layer.

推荐答案

是的，列表将存储您输入的对象。请参阅列表（Of T）。添加：

Yes, a list will store your objects as entered. See List(Of T).Add:

将对象添加到列表（Of T）的末尾。

Adds an object to the end of the List(Of T).

这篇关于列表（人）订单的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！