I am developing a point of sale program for a project subject. The trouble im having is when i press on the button to add the item from a textbox to a listview i receive an error: See attached Screenshot.
my code is:
Private Sub SalesScreen_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Me.CustomerTextBox.Text = "Cash Customer"
'Sets the properties of the listview
SalesScreenListView.View = View.Details
SalesScreenListView.GridLines = True
SalesScreenListView.FullRowSelect = True
'Add 4 columns and column names
SalesScreenListView.Columns.Add("Item", 100)
SalesScreenListView.Columns.Add("Description", 430)
SalesScreenListView.Columns.Add("Quantity", 70)
SalesScreenListView.Columns.Add("Price", 70)
'Set all Textbox properties to default
Me.SubTotalTextBox.Text = Format("0.00", "currency")
Me.TaxTextBox.Text = Format("0.00", "currency")
Me.TotalTextBox.Text = Format("0.00", "currency")
Dim InvoiceNum As String
InvoiceNum = IncrementInvoice(InvoiceNumberTextBox.Text)
Me.InvoiceNumberTextBox.Text = InvoiceNum
End Sub
Private Sub ProductCodeButton_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles ProductCodeButton.Click
Dim connection As New SqlClient.SqlConnection
connection.ConnectionString = ("Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database1.mdf;Integrated Security=True;User Instance=True")
connection.Open()
Dim adaptor As New SqlClient.SqlDataAdapter
Dim dataset As New DataSet
Try
'Search for data in the SQL database using an SQL Select statement.
Dim command As New SqlClient.SqlCommand("SELECT * FROM [Products] WHERE ProductID= '" & ProductCodeTextBox.Text & "'OR Description='" & ProductCodeTextBox.Text & "';", connection)
Dim dr As SqlClient.SqlDataReader = command.ExecuteReader(CommandBehavior.Default)
'Add rows to the listview for every match found in the database
While dr.Read()
Dim new_item As New _
ListViewItem(dr.Item("Item").ToString)
new_item.SubItems.Add(dr.Item("Description").ToString)
new_item.SubItems.Add(dr.Item("Quantity").ToString)
new_item.SubItems.Add(dr.Item("Price").ToString)
SalesScreenListView.Items.Add(new_item)
End While
dr.Close()
Catch ex As Exception
MsgBox(ex.ToString) 'Show error when something goes wrong
End Try
'Close database connection
connection.Close()
End Sub
Any help on what causes this error and how to correct it?