Programming for Everybody: November 2019

Retrieve data by timer VB.net - Example: essential English words- First Time



Imports System.Data.OleDb
Imports System.IO
Imports System.Configuration
Imports System.Data
Imports System.Data.DataTable
Public Class Form1
    Dim conn As New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=d:\english1.mdb")
    Dim myreader11 As OleDbDataReader
    Dim myreader5 As OleDbDataReader


    Private Sub Label1_Click(sender As Object, e As EventArgs) Handles Label1.Click

    End Sub

    Private Sub Label2_Click(sender As Object, e As EventArgs) Handles Label2.Click

    End Sub

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        If conn.State = ConnectionState.Closed Then
            conn.Open()
        End If


        Dim myreader1 As OleDbDataReader



        Dim strsql As String
        strsql = "select id from table1 where id =(select max(id) from table1)"
        Dim cmd1 As New OleDbCommand(strsql, conn)

        myreader1 = cmd1.ExecuteReader
        myreader1.Read()
        Label2.Text = myreader1("id")

        Timer2.Enabled = True


        conn.Close()


    End Sub

    Private Sub Timer2_Tick(sender As Object, e As EventArgs) Handles Timer2.Tick
        For aa As Integer = 0 To TextBox1.Text Step 1
            aa = TextBox1.Text + 1
            TextBox1.Text = aa



            Dim strsql As String
            strsql = "select id from table1 where id=" + TextBox1.Text + ""
            Dim cmd1 As New OleDbCommand(strsql, conn)
            If conn.State = ConnectionState.Closed Then
                conn.Open()
            End If

            myreader11 = cmd1.ExecuteReader



            If (myreader11.Read()) Or aa < Label2.Text Then

                'Try

                '    TextBox1.Text = myreader1("id")
                'Catch


                'End Try
                load1()


            Else
                Timer2.Enabled = False

                TextBox1.Text = Label2.Text


                MessageBox.Show("Words Ended")

                Return


            End If





        Next
        conn.Close()


    End Sub
    Private Sub load1()
        Try
            Dim conn5 As New OleDbConnection

            conn5.ConnectionString = ("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=d:\english1.mdb")
            If conn5.State = ConnectionState.Closed Then
                conn5.Open()
            End If
            Dim strsql5 As String
            strsql5 = "select * from table1 where id=" + TextBox1.Text + ""
            Dim cmd5 As New OleDbCommand(strsql5, conn5)
            myreader5 = cmd5.ExecuteReader

            myreader5.Read()

            Try
                Label3.Text = myreader5("word")
            Catch
            End Try
            Try


                Label4.Text = myreader5("ar")
            Catch
            End Try

            Try


                Label5.Text = myreader5("en")
            Catch
            End Try



            conn5.Close()
        Catch
        End Try
    End Sub


End Class