Vb.net 为什么我的循环不能正常工作visual basic

我是vb的初学者，每100家店的销售额我就要显示一个*；但是，在循环中重新打印之前输入的值。谢谢你的帮助

我想在列表中添加以下内容：

• 商店1：**
• 商店2*****

每*=100

Public Class Exercise6

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

        Const intNumberOfDays As Integer = 5           'days 
        Dim intSales As Decimal = 0             'to hold daily sales
        Dim strUserInput As String              'to hold user input
        Dim strAsterisks As String = ""          'Asterisks
        Const intAsterisk As Integer = 100
        Dim intAsteriskTotal As Integer
        Dim strDataOut As String = String.Empty    'holds the list output
        Dim intCounter As Integer = 1

        'gets sales for 5 stores
        Do While intCounter <= intNumberOfDays
            strUserInput = InputBox("Enter the sales for store" &
                                    intCounter.ToString(), "Store Sales is Needed")
            If strUserInput <> String.Empty And IsNumeric(strUserInput) Then
                intSales = CInt(strUserInput)


                'calculate the number of asterisk that must be display
                intAsteriskTotal = CInt(intSales / intAsterisk)

                strAsterisks = New String(CChar("*"), intAsteriskTotal)
                'add the store to the output string


                strDataOut &= "Store " & intCounter.ToString() & ": " & strAsterisks
                'add the output to the list box
                lstChart.Items.Add(strDataOut)
                intCounter += 1
            Else
                MessageBox.Show("Please enter a proper value for store sales.")
            End If

        Loop

    End Sub
End Class

公共课练习6
私有子btnDisplay\u单击（发送者作为对象，e作为事件参数）处理btnDisplay。单击
常量intNumberOfDays为整数=5'天
Dim intSales作为十进制=0'保存每日销售额
Dim strUserInput As String'以保存用户输入
暗条纹为字符串=“星号”
常量intAsterisk作为整数=100
Dim intAsteriskTotal为整数
Dim strDataOut As String=String.Empty'保存列表输出
整数为1的整数计数器
'获得5家店铺的销售额
当intCounter刚刚固定时执行。我变了

strDataOut &= "Store " & intCounter.ToString() & ": " & strAsterisks

与

代码中的问题是，您在每次迭代中都使用
strDataOut&=
将字符串追加到
strDataOut
中。因此，如果在循环开始时清除
strDataOut=“”
，则是正确的。因此，您的代码如下所示：

    Do While intCounter <= intNumberOfDays
        strUserInput = InputBox("Enter the sales for store" &
                                intCounter.ToString(), "Store Sales is Needed")
        strDataOut = "" '<---------- Additional line added
        If strUserInput <> String.Empty And IsNumeric(strUserInput) Then
            intSales = CInt(strUserInput)
            intAsteriskTotal = CInt(intSales / intAsterisk)
            strAsterisks = New String(CChar("*"), intAsteriskTotal)
            strDataOut &= "Store " & intCounter.ToString() & ": " & strAsterisks
            ListBox1.Items.Add(strDataOut)
            intCounter += 1
        Else
            MessageBox.Show("Please enter a proper value for store sales.")
        End If
    Loop

Do While intCounter
    Do While intCounter <= intNumberOfDays
        strUserInput = InputBox("Enter the sales for store" &
                                intCounter.ToString(), "Store Sales is Needed")
        strDataOut = "" '<---------- Additional line added
        If strUserInput <> String.Empty And IsNumeric(strUserInput) Then
            intSales = CInt(strUserInput)
            intAsteriskTotal = CInt(intSales / intAsterisk)
            strAsterisks = New String(CChar("*"), intAsteriskTotal)
            strDataOut &= "Store " & intCounter.ToString() & ": " & strAsterisks
            ListBox1.Items.Add(strDataOut)
            intCounter += 1
        Else
            MessageBox.Show("Please enter a proper value for store sales.")
        End If
    Loop