По данным о наименовании товара, его цене, и количеству, разработать проект для ввода данных и поиска

Public Class Form1
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        If IO.File.Exists("Data.txt") Then
            Dim tableData As String() = IO.File.ReadAllLines("Data.txt", System.Text.Encoding.Default)
            For Each tData As String In tableData
                DataGridView1.Rows.Add(tData.Split("|"))
            Next
            If DataGridView1.Rows.Count <> 0 Then
                Button3.Enabled = True
                Button5.Enabled = True
            End If
        End If
    End Sub
 
    Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
        Dim tableData As New List(Of String)
        For Each tData As DataGridViewRow In DataGridView1.Rows
            tableData.Add(tData.Cells(0).Value & "|" & tData.Cells(1).Value & "|" & tData.Cells(2).Value & "|" & tData.Cells(3).Value)
        Next
        IO.File.WriteAllLines("Data.txt", tableData.Cast(Of String).ToArray, System.Text.Encoding.Default)
        MsgBox("Данные сохранены.")
    End Sub
 
    Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
        DataGridView1.Rows.Add()
        DataGridView1.Select()
        DataGridView1.Item(0, DataGridView1.Rows.Count - 1).Selected = True
        If DataGridView1.Rows.Count <> 0 Then
            Button3.Enabled = True
            Button5.Enabled = True
        End If
    End Sub
 
    Private Sub Button5_Click(sender As Object, e As EventArgs) Handles Button5.Click
        If DataGridView1.SelectedRows IsNot Nothing Then
            DataGridView1.Rows.RemoveAt(DataGridView1.CurrentRow.Index)
            If DataGridView1.Rows.Count = 0 Then
                Button3.Enabled = False
                Button5.Enabled = False
            End If
        End If
    End Sub
 
    Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
        Dim gName As String = InputBox("Введите 'Наименование товара'", "Поиск")
        If gName.Length <> 0 Then
            Dim isFound As Boolean = False
            Dim indx As Integer
 
            For Each r As DataGridViewRow In DataGridView1.Rows
                If r.Cells(0).Value.ToString.ToLower = gName.ToLower Then
                    isFound = True
                    indx = r.Index
                    Exit For
                End If
            Next
 
            If isFound Then
                With DataGridView1
                    .Select()
                    .Item(0, indx).Selected = True
                End With
            End If
        End If
    End Sub
 
    Private Sub DataGridView1_CellPainting(sender As Object, e As DataGridViewCellPaintingEventArgs) Handles DataGridView1.CellPainting
        Dim cnt As Double
        For Each r As DataGridViewRow In DataGridView1.Rows
            r.Cells(3).Value = Val(r.Cells(1).Value) * Val(r.Cells(2).Value)
            cnt += Val(r.Cells(3).Value)
        Next
        Label2.Text = "Общая сумма всех товаров: " & cnt
    End Sub
End Class