I have this code which displays a login form, i want to encrypt the password before it stores into the sql database and should also be able to verify the pwd when a user logs in.
Please help me, it'll be very greateful of you, Thank you.

Private Sub Login_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Login.Click

    Try

        If constring.State = ConnectionState.Open Then
            constring.Close()
        End If
        constring.Open()

        Dim MainMenu As New MDIParent1
        Dim result As String
        Dim CMD As New SqlCommand
        CMD.Connection = constring


        CMD.CommandText = "Exec validatelogin '" & txtuserid.Text & "','" & txtpwd.Text & "'"
        Dim ad As New SqlDataAdapter(CMD)
        Dim dt As New DataTable

        result = CMD.ExecuteScalar
        ad.Fill(dt)
        MsgBox(result, MsgBoxStyle.Exclamation)


        If result = "True" And CheckBox1.CheckState = 0 Then

            MainMenu.Show()
            Me.Dispose(False)

        Else
            MsgBox("Username or Password appears to be wrong")

        End If


        constring.Close()
    Catch ex As Exception
        MsgBox(ex.Message, MsgBoxStyle.ApplicationModal)
    End Try


End Sub


Private Sub CheckBox1_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged

    Dim result As String
    Dim CMD As New SqlCommand
    CMD.Connection = constring

    Try
        If constring.State = ConnectionState.Open Then
            constring.Close()
        End If
        constring.Open()


        If CheckBox1.CheckState = 1 Then
            CMD.CommandText = "Exec validatelogin '" & txtuserid.Text & "','" & txtpwd.Text & "'"
            Dim ad As New SqlDataAdapter(CMD)
            Dim dt As New DataTable

            result = CMD.ExecuteScalar
            ad.Fill(dt)

            If result = "True" Then
                Height = 655
                Width = 466

            Else
                MsgBox("Username or Password appears to be wrong")
            End If

        ElseIf CheckBox1.CheckState = 0 Then
            Height = 289
            Width = 462

        End If

        constring.Close()

    Catch ex As Exception
        MsgBox(ex.Message, MsgBoxStyle.ApplicationModal)
    End Try


End Sub


Private Sub btnSave_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click

    Try

        Dim sqlparameter(2) As Object
        sqlparameter(0) = txtuserid.Text
        sqlparameter(1) = txtoldpwd.Text
        sqlparameter(2) = txtnewpwd.Text


        While CheckBox1.CheckState = 1
            If constring.State = ConnectionState.Open Then
                constring.Close()
            End If

            constring.Open()
            Dim CMD As New SqlCommand
            CMD.Connection = constring
            Dim commandstring As String = " '"
            Dim msg As String
            Dim ad As New SqlDataAdapter
            Dim dt As New DataTable



            For Each Str As String In sqlparameter
                commandstring &= Str & "','"
            Next

            If String.IsNullOrEmpty(txtuserid.Text) OrElse String.IsNullOrEmpty(txtpwd.Text) OrElse String.IsNullOrEmpty(txtoldpwd.Text) OrElse String.IsNullOrEmpty(txtnewpwd.Text) Then

                MsgBox("All fields need to be filled")
                Exit Sub

            End If

            commandstring = Mid(commandstring, 1, (Len(commandstring) - 2))

            CMD.CommandText = "Exec updatelog " & commandstring
            msg = CMD.ExecuteScalar()
            'ad.Fill(dt)


            If txtoldpwd.Text = txtpwd.Text Then
                MsgBox("password changed")
                Exit Sub
            Else
                MsgBox("password is mismatched")
                Exit Sub
            End If
            constring.Close()

        End While

    Catch ex As Exception
        MsgBox(ex.Message, MsgBoxStyle.ApplicationModal)


    End Try


End Sub
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