顺序文件显示＆＃34; System.Windows.Forms.ListBox + SelectedObjectCollection＆＃34;尝试添加选定的列表框项目时

Question

我正在开发一个程序，用户必须从列表框中选择项目（lstCommercial）并保存到访问文件，问题是只有最后选择的项目显示在访问文件中，这里是我的代码

Public Class Form1

    Dim outfile As IO.StreamWriter
    Dim infile As IO.StreamReader

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        lstCommercial.Items.Add("Cheerios")
        lstCommercial.Items.Add("Doritos")
        lstCommercial.Items.Add("T-mobile")
        lstCommercial.Items.Add("Radioshack")
    End Sub

    Private Sub btnSave_Click(sender As Object, e As EventArgs) Handles btnSave.Click

        ' open the file to create
        outfile = IO.File.CreateText("commercial.txt")

        ' write the name on a separate line in the file
        outfile.WriteLine(lstCommercial.SelectedItems)

        ' close the file
        lstCommercial.Focus()
        outfile.Close()
    End Sub

    Private Sub btnDisplay_Click(sender As Object, e As EventArgs) Handles btnDisplay.Click

    End Sub
    Private Sub btnExit_Click(sender As Object, e As EventArgs) Handles btnExit.Click
        Me.Close()
    End Sub

End Class

Answer 1

而不是：

' write the name on a separate line in the file
outfile.WriteLine(lstCommercial.SelectedItems)

...试试这个：

' write the name on a separate line in the file
For Each item In lstCommercial.SelectedItems
    outfile.WriteLine(item)
Next

问题在于您没有迭代SelectedItems集合中的所有元素。另外，请确保将lstCommercial ListBox的SelectionMode属性设置为MultiSimple或MultiExtended，并确保在点击btnSave时实际选择了多个项目。