Vb.net 输入投票复选框后可以更新数据库（ms.access）

这是登录系统的代码

Imports System.Data.OleDb
Module koneksi
    Public conn As OleDbConnection = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=D:\pemilu.accdb")
    Public da As OleDbDataAdapter
    Public ds As DataSet
    Public cmd As OleDbCommand
    Public rd As OleDbDataReader
    Public dgv As New DataGridView
End Module
Public Class Form2
    Private Sub Form2_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        PasswordTextBox.UseSystemPasswordChar = True
        NimTextBox.Focus()
    End Sub

    Private Sub btnpilih_Click(sender As Object, e As EventArgs) Handles btnpilih.Click
        conn.Close()
        conn.Open()
        cmd = New OleDbCommand("SELECT * FROM pemilih WHERE nim = '" &
                           NimTextBox.Text & "' AND password = '" &
                           PasswordTextBox.Text & "'", conn)
        rd = cmd.ExecuteReader
        Dim userfound As Boolean = False
        Dim firstname As String = ""
        Dim lastname As String = ""

        While rd.Read
            If NimTextBox.Text = rd("nim").ToString And PasswordTextBox.Text = rd("password").ToString Then
                userfound = True
                firstname = rd("firstname").ToString
                lastname = rd("lastname").ToString
            End If
        End While

        If userfound = True Then
            MsgBox("Pilihlah Pemimpin Sesuai Hati Nurani Anda. Selamat Memilih.", MsgBoxStyle.Information, "Selamat Memilih")
            NimTextBox.Text = ""
            PasswordTextBox.Text = ""
            Form1.Label1.Text = "Selamat Memilih, " & firstname & " " & lastname
            Me.Hide()
            Form1.Show()
        Else
            MsgBox("Maaf, NIM Atau Password Anda Masukkan Salah Atau NIM Anda Belum Terdaftar. Silahkan Ulangi Kembali.", MsgBoxStyle.Information, "Info")
            NimTextBox.Focus()
        End If
    End Sub

    Private Sub PasswordTextBox_Keypress(sender As Object, e As System.Windows.Forms.KeyPressEventArgs) Handles PasswordTextBox.KeyPress
        If e.KeyChar = Chr(13) Then
            btnpilih_Click(Me, EventArgs.Empty)
        End If

    End Sub

    Private Sub CheckBox1_CheckedChanged(sender As Object, e As EventArgs) Handles CheckBox1.CheckedChanged
        If CheckBox1.Checked Then
            PasswordTextBox.UseSystemPasswordChar = False
        Else
            PasswordTextBox.UseSystemPasswordChar = True
        End If
    End Sub
End Class

它工作在最佳状态

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这是投票代码

Imports System.Data.OleDb
Public Class Form1
    Private Sub btnpilih_Click(sender As Object, e As EventArgs) Handles btnpilih.Click
        conn.Close()
        conn.Open()

        If ckagus.Checked And cksuyamto.Checked And ckfarid.Checked Then
            MsgBox("Anda hanya bisa memilih satu kandidat", MsgBoxStyle.Information, "Info")
        ElseIf ckagus.Checked And cksuyamto.Checked Then
            MsgBox("Anda hanya bisa memilih satu kandidat", MsgBoxStyle.Information, "Info")
        ElseIf ckagus.Checked And ckfarid.Checked Then
            MsgBox("Anda hanya bisa memilih satu kandidat", MsgBoxStyle.Information, "Info")
        ElseIf cksuyamto.Checked And ckfarid.Checked Then
            MsgBox("Anda hanya bisa memilih satu kandidat", MsgBoxStyle.Information, "Info")
        ElseIf ckagus.Checked Then
            cmd = New OleDbCommand("UPDATE kandidat SET [agus] = agus + 1", conn)
            cmd.ExecuteNonQuery()
            MsgBox("Terimakasih karena sudah memilih", MsgBoxStyle.Information, "Info")
            Me.Hide()
            Form2.Show()
            Form2.NimTextBox.Focus()
        ElseIf cksuyamto.Checked Then
            cmd = New OleDbCommand("UPDATE kandidat SET [suyamto] = suyamto + 1", conn)
            cmd.ExecuteNonQuery()
            MsgBox("Terimakasih karena sudah memilih", MsgBoxStyle.Information, "Info")
            Me.Hide()
            Form2.Show()
            Form2.NimTextBox.Focus()
        ElseIf ckfarid.Checked Then
            cmd = New OleDbCommand("UPDATE kandidat SET [farid] = farid + 1", conn)
            cmd.ExecuteNonQuery()
            MsgBox("Terimakasih karena sudah memilih", MsgBoxStyle.Information, "Info")
            Me.Hide()
            Form2.Show()
            Form2.NimTextBox.Focus()
        End If
        ckagus.CheckState = CheckState.Unchecked
        cksuyamto.CheckState = CheckState.Unchecked
        ckfarid.CheckState = CheckState.Unchecked
    End Sub

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        If Label1.Text = "Selamat Memilih, Admin " Then
            btnreport.Visible = True
        End If
    End Sub
End Class

问题是：

根据投票代码，我不能在选择候选人时对kandidat表上的值字段求和

我的代码错了吗？但是，当我运行程序时没有错误，并且kandidat表的值从未增加。

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使用这么多代码可能很难获得论坛帮助。我建议您创建一个小项目，只需要测试和证明您的问题。这通常是一种很好的故障排除技术，也会让您更快地获得帮助。@GlennHolden我应该制作一个视频吗？只有在需要交流正在发生的事情时才可以。在这种情况下，我认为视频的杀伤力过大，只会显示什么都没有发生。这对你来说是一个很好的解决问题的方法。99%的时间我都是这样解决我自己的问题。可能很难用这么多代码获得论坛的帮助。我建议您创建一个小项目，只需要测试和证明您的问题。这通常是一种很好的故障排除技术，也会让您更快地获得帮助。@GlennHolden我应该制作一个视频吗？只有在需要交流正在发生的事情时才可以。在这种情况下，我认为视频的杀伤力过大，只会显示什么都没有发生。这对你来说是一个很好的解决问题的方法。99%的时间我都是这样解决自己的问题。