visual-studio - 需要帮助修复未处理的异常
问题描述
我收到以下错误:
System.ArgumentOutOfRangeException: '索引和长度必须引用字符串中的位置。参数名称:长度'
(在代码 *** 上查找粗体斜体字,这就是我要修复的地方)
不确定是什么问题。这是整个代码:
Imports GroceryApp.GroceryItem
Imports System.IO
Public Class GroceryItemForm
Private strFileName As String = String.Empty
Private Sub btnAddToBasket_Click(sender As Object, e As EventArgs) Handles btnAddToBasket.Click, AddToolStripMenuItem.Click
Dim gi As GroceryItem
Dim price As Double
' Validate that brand name is entered
If txtBrandName.Text = "" Then
MsgBox("Please input an Brand Name", , "Value Required")
txtBrandName.Focus()
Exit Sub
End If
' Validate that price is entered
If Not Double.TryParse(numPrice.Text, price) Then
MsgBox("Please input an Price", , "Value Required")
numPrice.Focus()
Exit Sub
End If
' Validate that Aisle is selected
If cboAisle.Text = "" Then
MsgBox("Please select an Aisle", , "Value Required")
cboAisle.Focus()
Exit Sub
End If
***txtScanNumber.Text = txtBrandName.Text.Substring(0, 3) & "1019"***
gi = New GroceryItem(txtScanNumber.Text, txtBrandName.Text, price)
gi.Type = [Enum].Parse(GetType(Aisle), cboAisle.Text)
gi.Description = txtDescription.Text
basket.Add(gi)
End Sub
Private Sub ExitToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ExitToolStripMenuItem.Click
Application.Exit()
End Sub
Private Sub ViewToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ViewToolStripMenuItem.Click
'Dim result As String = ""
'Dim i As Integer = 1
'For Each gi As GroceryItem In basket
'result = result & "Item " & i & vbNewLine & "Aisle: " & gi.Type.ToString & vbNewLine & "Scan Number: " & gi.ScanNumber & vbNewLine & "Brand Name: " & gi.BrandName & vbNewLine & vbNewLine
'i = i + 1
'Next
'MsgBox(result, , "Basket Details")
Dim oForm As BasketDisplayForm
oForm = New BasketDisplayForm()
oForm.Show()
oForm = Nothing
End Sub
Private Sub GroceryItemForm_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim oForm As LoginForm
oForm = New LoginForm()
oForm.Show()
oForm = Nothing
End Sub
Private Sub SaveToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles SaveToolStripMenuItem.Click
Dim rowLine As String = ""
'If strFileName = String.Empty Then
If SaveFileDialog1.ShowDialog = Windows.Forms.DialogResult.OK Then
strFileName = SaveFileDialog1.FileName
Dim fsStream As New FileStream(strFileName, FileMode.Append, FileAccess.Write)
Dim sw As New StreamWriter(fsStream)
Dim sb As New System.Text.StringBuilder
For Each Item As GroceryItem In basket
sb.AppendLine(String.Concat(Item.ScanNumber, ",", Item.Type.ToString, ",", Item.BrandName, ",", Item.Description, ",", Item.Price))
'rowLine = rowLine + Item.ScanNumber + "," + Item.Type.ToString + "," + Item.BrandName + "," + Item.Description + "," + Item.Price.ToString
Next
'IO.File.WriteAllText(strFileName, sb.ToString)
'rowLine = rowLine.Remove(rowLine.Length - 1, 1)
sw.WriteLine(sb)
sw.Flush()
MsgBox("Data Saved Successfully")
sw.Close()
basket.Clear()
End If
'End If
End Sub
Private Sub LoadToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles LoadToolStripMenuItem.Click
Dim basketFile As StreamReader
Dim gi As GroceryItem
Dim sNo, brand, desc, aisle As String
Dim price As Double
Dim y As Integer
basket.Clear()
If OpenFileDialog1.ShowDialog = Windows.Forms.DialogResult.OK Then
strFileName = OpenFileDialog1.FileName
basketFile = File.OpenText(strFileName)
' Read Power rating from file
Using sr As StreamReader = New StreamReader(strFileName)
Do While sr.Peek() > -1
For Each c As String In sr.ReadToEnd().Split(CType(Chr(10), Char))
sNo = ""
For Each d As String In c.Split(",")
If y = 0 Then
sNo = d
End If
If y = 1 Then
aisle = d
End If
If y = 2 Then
brand = d
End If
If y = 3 Then
desc = d
End If
If y = 4 Then
price = d
End If
y += 1
Next
If (sNo <> "") Then
gi = New GroceryItem(sNo, brand, price)
gi.Type = [Enum].Parse(GetType(Aisle), aisle)
gi.Description = desc
If (sNo <> "" & vbCr & "") Then
basket.Add(gi)
End If
End If
y = 0
Next
Loop
End Using
basketFile.Close()
End If
End Sub
End Class
解决方案
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