checkboxlist ausgewählte Items wird nicht ausgewählt und fügt leere Werte in string

Question

Ich habe ein Formular, in dem Daten eingefügt werden. Es gibt einige Checkbox-Listen. CheckboxList bindet mit Tabelle in db. Jetzt nach der Auswahl von Elementen sollte es ausgewählte Werte in der Tabelle db eingeben, aber es fügt leere Strings ein.

Ich habe zwei checkboxlist (Produkte, Zahlung) Zahlung funktioniert gut. Problem ist in Produkten.

VB-Code

Private Sub list_business_hospital_Load(sender As Object, e As EventArgs) Handles Me.Load 
    Me.PopulateProducts() 
    Me.PopulatePayments() 
End Sub 

Private Sub PopulateProducts() 
    productsList.Items.Clear() 
    Using conn As New MySqlConnection() 
     conn.ConnectionString = ConfigurationManager _ 
      .ConnectionStrings("conio").ConnectionString() 
     Using cmd As New MySqlCommand() 
      cmd.CommandText = "select * from chemistsProducts" 
      cmd.Connection = conn 
      conn.Open() 
      Using sdr As MySqlDataReader = cmd.ExecuteReader() 
       While sdr.Read() 
        Dim item As New ListItem() 
        item.Text = sdr("productName").ToString() 
        item.Value = sdr("productName").ToString() 
        'item.Selected = Convert.ToBoolean(sdr("IsSelected")) 
        productsList.Items.Add(item) 
       End While 
      End Using 
      conn.Close() 
     End Using 
    End Using 
    productsList.Items.Insert(0, New ListItem("All", "All")) 
End Sub 

Private Sub PopulatePayments() 
    Using conn As New MySqlConnection() 
     conn.ConnectionString = ConfigurationManager _ 
      .ConnectionStrings("conio").ConnectionString() 
     Using cmd As New MySqlCommand() 
      cmd.CommandText = "select * from payment" 
      cmd.Connection = conn 
      conn.Open() 
      Using sdr As MySqlDataReader = cmd.ExecuteReader() 
       While sdr.Read() 
        Dim item As New ListItem() 
        item.Text = sdr("paymentName").ToString() 
        item.Value = sdr("paymentID").ToString() 
        'item.Selected = Convert.ToBoolean(sdr("IsSelected")) 
        ListPayment.Items.Add(item) 
       End While 
      End Using 
      conn.Close() 
     End Using 
    End Using 
    ListPayment.Items.Insert(0, New ListItem("All", "All")) 
End Sub 

Private Sub save_Click(sender As Object, e As EventArgs) Handles save.Click 
     Dim selectedProducts As String = String.Empty 
     For Each chk As ListItem In productsList.Items 
      If chk.Selected = True Then 
       selectedProducts &= "<li>" + chk.Text + "</li>" 
      End If 
     Next 


     Dim payments As String = String.Empty 
     For Each chk As ListItem In ListPayment.Items 
      If chk.Selected = True Then 
       payments &= "<li>" + chk.Text + "</li>" 
      End If 
     Next 

     Try 
      Dim str1 As String = "INSERT INTO chemists (`products`, `payment`) values ('" + selectedProducts + "', '" + payments + "')" 

      Dim str2 As MySqlDataReader 
      Dim adapter As New MySqlDataAdapter 
      Dim command As New MySqlCommand 
      command.CommandText = str1 
      command.Connection = con 
      adapter.SelectCommand = command 
      con.Open() 
      str2 = command.ExecuteReader 
      con.Close() 
      Response.Redirect("business-added.aspx") 
     Catch ex As Exception 
      Response.Write(ex) 
     End Try 
End Sub 

Hier Zahlung wird eingefügt, was ich ausgewählt haben. Das Problem ist in selectedProducts

Answer 1

Versuchen unten Seite zu laden,

If Not IsPostBack Then 
    Me.PopulateProducts() 
    Me.PopulatePayments() 
End If