Question

需要一个可以创建值为0-50的数组的程序，然后将它们输出到列表中。它似乎只输出'int 32'。什么错误的想法？

    Public Class Form1
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Dim Numbers(50) As Integer
        Dim Index As Integer
        Do Until Numbers(Index) <= 50
            Index = Index + 1
            Numbers(Index) = Index
        Loop
        lstnumbers.Items.Add(Numbers)
    End Sub
End Class

Answer 1

一些小改动...... Do Until＆lt;会给出一堆零还移动了一些东西以避免Index超出范围并在那里得到零。

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Dim Numbers(50) As Integer
        Dim Index As Integer
        Do Until Index >= 51
            Numbers(Index) = Index
            lstNumbers.Items.Add(Numbers(Index))
            Index = Index + 1
        Loop

Answer 2

这里有两个选项：

<强>一：

   Public Class Form1
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Dim lstnumbers As New ArrayList()
        Dim Numbers(50) As Integer
        Dim Index As Integer
        Do Until Numbers(Index) <= 50
            Index = Index + 1
            Numbers(Index) = Index
        Loop
        lstnumbers.AddRange(Numbers)
    End Sub
End Class

<强>两个

Public Class Form1
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Dim Numbers(50) As Integer
        Dim Index As Integer
        Do Until Numbers(Index) <= 50
            Index = Index + 1
            Numbers(Index) = Index
            lstnumbers.Items.Add(Index)
        Loop
    End Sub
End Class

这是因为Items.Add 每次只收一件商品，这意味着Items.Add(Numbers)只会添加int 32。

ArrayList AddRange会占用一个队列并添加它的范围，但是如果你知道你的ArrayList确切包含多少元素，则不建议使用它，因为它＆＃39;大小是动态变化的。

在这个例子中没有区别，因为你已经使用了一个列表。

数组程序只输出“int 32”

2 个答案: