Question

到目前为止，我有这个，虽然我遗漏了一些东西。我应该使用数组来填充列表框中的.txt中的项目，然后当单击列表框中的项目时，标签会以价格更新。有什么建议吗？

Public Class frmMain

Structure product
    Public itemnumber As String
    Public itemprice As Decimal
End Structure

Private Sub ButtonExit_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles ButtonExit.Click
    Me.Close()
End Sub


Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

    Dim ItemInfo As String = "H:\Users\user\Documents\Visual Studio 2012\Projects\WindowsApplication9\ItemInfo.txt"
    Dim inFile As IO.StreamReader
    Dim strName As String
    Dim skipLine As Boolean


    If System.IO.File.Exists("H:\Users\user\Documents\Visual Studio 2012\Projects\WindowsApplication9\ItemInfo.txt") = True Then
        inFile = IO.File.OpenText("H:\Users\user\Documents\Visual Studio 2012\Projects\WindowsApplication9\ItemInfo.txt")
        Do Until inFile.Peek = -1
            strName = inFile.ReadLine
            If skipLine = False Then
                ListBox1.Items.Add(strName)
                skipLine = True
            Else : skipLine = False
            End If
        Loop

        Dim objReader As New System.IO.StreamReader(ItemInfo)
        ListBox1.Text = objReader.ReadToEnd
        objReader.Close()
    Else

        MsgBox("File Does Not Exist")

    End If
End Sub

End Class

Answer 1

这是一个很大的提示：

Imports System.IO
Public Class Form1

    Dim myItems As List(Of Product)
    Class Product
        Public ItemNumber As String
        Public ItemPrice As Decimal
    End Class

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

        Dim itemInfo As String = "H:\Users\user\Documents\Visual Studio 2012\Projects\WindowsApplication9\ItemInfo.txt"

        If File.Exists(itemInfo) Then
            myItems = New List(Of Product)
            Dim allItems = File.ReadAllLines(itemInfo)

            For Each line As String In allItems

                ' see http://msdn.microsoft.com/en-us/library/ms131448%28v=vs.110%29.aspx for String.Split
                Dim parts() As String = line.Split({" "c}, StringSplitOptions.RemoveEmptyEntries)
                ' only process lines with two parts
                If parts.Count = 2 Then
                    Dim itemEntry As New Product
                    itemEntry.ItemNumber = parts(0)
                    'TODO: (optional) use Decimal.TryParse to make sure the entry really can be parsed as a Decimal.
                    itemEntry.ItemPrice = CDec(parts(1))
                    myItems.Add(itemEntry)
                End If

            Next

        Else
            'HINT: always give as much info as is reasonable when saying something went wrong.
            MsgBox("File """ & itemInfo & """ does not exist or could not be opened.")
        End If

        'TODO: show the items by getting the .ItemNumber of each item in myItems
    End Sub

End Class

尝试从.txt文件中读取以填充ListBox和Label

1 个答案: