Код по щелчку следующей кнопки

Question

Следующий мой код, я делаю проект на онлайн-экзамене, потому что у меня есть модуль вопроса для отображения в этом случае, когда я нажимаю на следующую кнопку, он должен перейти к следующему вопросу, но он не будет

Imports System.Data.SqlClient 
Partial Class Questions 
Inherits System.Web.UI.Page 

Dim cmd As New SqlCommand 
Dim Result As Integer = 0 
Dim Question_ID As Integer = Nothing 
Dim strconn As String = ConfigurationManager.ConnectionStrings("DefaultConnection").ConnectionString 
Dim con As New SqlConnection(strconn) 
Protected Sub rblQuestion_SelectedIndexChanged(sender As Object, e As EventArgs) Handles rblQuestion1.SelectedIndexChanged 
    CheckAnswer(rblQuestion1.SelectedValue, lblQuestion1.Text) 
End Sub 

Private Sub CheckAnswer(ByVal Answer As String, ByVal Question As String) 
    Dim RetrievedAnswer As String = Nothing 

    Try 
     Dim daQuestionID As New SqlDataAdapter("select Question_ID from tblQuestions where Question='" & Question & "'", con) 
     Dim dsQuestionID As New Data.DataSet 
     Dim dtQuestionID As New Data.DataTable 

     If Not con.State = Data.ConnectionState.Open Then con.Open() 
     daQuestionID.Fill(dsQuestionID) 
     dtQuestionID = dsQuestionID.Tables(0) 

     If Not dtQuestionID.Rows.Count <= 0 Then 
      If Not IsDBNull(dtQuestionID.Rows(0).Item("Question_ID")) Then 
       Question_ID = dtQuestionID.Rows(0).Item("Question_ID") 

      Else 
       Exit Sub 
      End If 
     End If 
    Catch ex As Exception 

    End Try 

    Try 
     Dim daAnswer As New SqlDataAdapter("select Answer from tblQuestions where Question_ID=" & Question_ID, con) 
     Dim dsAnswer As New Data.DataSet 
     Dim dtAnswer As New Data.DataTable 

     If Not con.State = Data.ConnectionState.Open Then con.Open() 
     daAnswer.Fill(dsAnswer) 
     dtAnswer = dsAnswer.Tables(0) 

     If Not dtAnswer.Rows.Count <= 0 Then 
      If Not IsDBNull(dtAnswer.Rows(0).Item("Answer")) Then 
       RetrievedAnswer = dtAnswer.Rows(0).Item("Answer") 
      End If 
     End If 

     If RetrievedAnswer = Answer Then 
      Try 
       Dim sr As New IO.StreamReader(System.AppDomain.CurrentDomain.BaseDirectory & "\\result.txt") 
       Result = sr.ReadLine 
       sr.Close() 
       Result = Result + 1 
       Dim sw As New IO.StreamWriter(System.AppDomain.CurrentDomain.BaseDirectory & "\\result.txt") 
       sw.WriteLine(Result) 
       sw.Close() 
      Catch ex As Exception 

      End Try 

     End If 
    Catch ex As Exception 

    End Try 
End Sub 
Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load 

    If Not IsPostBack Then 
     Try 
      Dim daQuestions As New SqlDataAdapter("SELECT TOP 20 * FROM tblQuestions ORDER BY NEWID()", con) 
      Dim dsQuestions As New Data.DataSet 
      Dim dtQuestions As New Data.DataTable 

      If Not con.State = Data.ConnectionState.Open Then con.Open() 
      daQuestions.Fill(dsQuestions) 
      dtQuestions = dsQuestions.Tables(0) 

      If Not dtQuestions.Rows.Count <= 0 Then 
       'For Question 1 
       If Not IsDBNull(dtQuestions.Rows(0).Item("Question")) Then 
        lblQuestion1.Text = dtQuestions.Rows(0).Item("Question") 
       End If 
       If Not IsDBNull(dtQuestions.Rows(0).Item("Option1")) Then 
        rblQuestion1.Items(0).Text = dtQuestions.Rows(0).Item("Option1") 
       End If 
       If Not IsDBNull(dtQuestions.Rows(0).Item("Option2")) Then 
        rblQuestion1.Items(1).Text = dtQuestions.Rows(0).Item("Option2") 
       End If 
       If Not IsDBNull(dtQuestions.Rows(0).Item("Option3")) Then 
        rblQuestion1.Items(2).Text = dtQuestions.Rows(0).Item("Option3") 
       End If 
       If Not IsDBNull(dtQuestions.Rows(0).Item("Option4")) Then 
        rblQuestion1.Items(3).Text = dtQuestions.Rows(0).Item("Option4") 
       End If 
      End If 
    Catch ex As Exception 

     End Try 




     'con.ConnectionString = ConfigurationManager.ConnectionStrings("DefaultConnection").ConnectionString 
     cmd = New SqlCommand("insert into tblQuestions (Question, Option1, Option2, Option3, Option4,) values (@question, @option1, @option2, @option3, @option4)", con) 
     cmd.Parameters.AddWithValue("@question", lblQuestion1.Text) 
     cmd.Parameters.AddWithValue("@option1", rblQuestion1.Text) 
     cmd.Parameters.AddWithValue("@option2", rblQuestion1.Text) 
     cmd.Parameters.AddWithValue("@option3", rblQuestion1.Text) 
     cmd.Parameters.AddWithValue("@option4", rblQuestion1.Text) 
     'cmdInsertQuestion.Parameters.AddWithValue("@answer", txtAnswer.Text) 
     Try 
      con.Open() 
      cmd.ExecuteNonQuery() 
      con.Close() 
      MsgBox(" ") 
      'txtAnswer.Text = "" 
      rblQuestion1.Text = "" 
      rblQuestion1.Text = "" 
      rblQuestion1.Text = "" 
      rblQuestion1.Text = "" 
     Catch ex As Exception 
      'ex.Message 
     End Try 
    End If 
End Sub 



Protected Sub rblQuestion1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles rblQuestion1.SelectedIndexChanged 

End Sub 

Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Button1.Click 


    If Not IsPostBack Then 
     Try 
      Dim daQuestions As New SqlDataAdapter("SELECT TOP 20 * FROM tblQuestions ORDER BY NEWID()", con) 
      Dim dsQuestions As New Data.DataSet 
      Dim dtQuestions As New Data.DataTable 

      If Not con.State = Data.ConnectionState.Open Then con.Open() 
      daQuestions.Fill(dsQuestions) 
      dtQuestions = dsQuestions.Tables(0) 

      If Not dtQuestions.Rows.Count <= 0 Then 
       'For Question 1 
       If Not IsDBNull(dtQuestions.Rows(0).Item("Question")) Then 
        lblQuestion1.Text = dtQuestions.Rows(0).Item("Question") 
       End If 
       If Not IsDBNull(dtQuestions.Rows(0).Item("Option1")) Then 
        rblQuestion1.Items(0).Text = dtQuestions.Rows(0).Item("Option1") 
       End If 
       If Not IsDBNull(dtQuestions.Rows(0).Item("Option2")) Then 
        rblQuestion1.Items(1).Text = dtQuestions.Rows(0).Item("Option2") 
       End If 
       If Not IsDBNull(dtQuestions.Rows(0).Item("Option3")) Then 
        rblQuestion1.Items(2).Text = dtQuestions.Rows(0).Item("Option3") 
       End If 
       If Not IsDBNull(dtQuestions.Rows(0).Item("Option4")) Then 
        rblQuestion1.Items(3).Text = dtQuestions.Rows(0).Item("Option4") 
       End If 
      End If 
     Catch ex As Exception 

     End Try 


    End If 
End Sub 

Protected Sub SqlDataSource1_Selecting(sender As Object, e As SqlDataSourceSelectingEventArgs) Handles SqlDataSource1.Selecting 

End Sub 
End Class 

Answer 1

Событие с нажатием кнопки в WebForms всегда является обратной передачей.

Итак, имея If Not IsPostBack Then в качестве первого элемента в обработчике нажатия кнопки, всегда будет останавливать код внутри инструкции при запуске.