ดูโค้ดให้หน่อยคะมันเออเรอไรไม่รุ้คะ ไม่รุ้ว่ามันเกี่ยวกะดาต้าเบสหรือป่าวกะไม่รุ้นะคะ ใครรู้ รบกวนดูดค

Option Explicit On
Option Strict On
Imports System.Text
Imports System.Data
Imports System.Data.SqlClient
Public Class fromLogin
    Dim Conn As SqlConnection
    Dim com As SqlCommand
    Dim dr As SqlDataReader
    Dim tr As SqlTransaction
    Dim sb As StringBuilder
    Public Shared str As String
    Dim status As String
    Private Sub fromLogin_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim strConn As String
        strConn = DBConnString.strConn
        Conn = New SqlConnection()
        With Conn
            If .State = ConnectionState.Open Then .Close()
            .ConnectionString = strConn
            .Open()
        End With
        txtUserName.Focus()
    End Sub
    Private Sub Login()
        sb = New StringBuilder()
        sb.Append("SELECT User_Name,User_Type FROM tb_User")
        sb.Append(" WHERE User_Name=@User_Name")
        Dim sqlLogin As String
        sqlLogin = sb.ToString()
        com = New SqlCommand()
        With com
            .CommandText = sqlLogin
            .CommandType = CommandType.Text
            .Connection = Conn
            .Parameters.Clear()
            .Parameters.Add("@User_Name", SqlDbType.VarChar).Value = txtUserName.Text
            dr = .ExecuteReader()
            If dr.HasRows Then
                With dr
                    .Read()
                    status = .GetString(.GetOrdinal("User_Type"))
                End With
            End If
        End With
        dr.Close()
        '***************************************************************************************************
        If status = "พนักงาน" Then
            sb = New StringBuilder()
            sb.Append("SELECT User_Name,User_Password FROM tb_User")
            sb.Append(" WHERE (User_Name=@User_Name)")
            sb.Append(" AND (User_Password=@User_Password)")

            sqlLogin = sb.ToString()
            com = New SqlCommand()
            With com
                .CommandText = sqlLogin
                .CommandType = CommandType.Text
                .Connection = Conn
                .Parameters.Clear()
                .Parameters.Add("@User_Name", SqlDbType.VarChar).Value = txtUserName.Text
                .Parameters.Add("@User_Password", SqlDbType.VarChar).Value = txtPassword.Text
                dr = .ExecuteReader()
                If dr.HasRows Then
                    str = "0"
                    fromMainn.Show()
                    Me.Hide()
                Else
                    MessageBox.Show("UserName หรือ Password ที่คุณป้อน ไม่ถูกต้อง !!!", "ผลการทำงาน", MessageBoxButtons.OK, MessageBoxIcon.Exclamation)
                End If
            End With
            dr.Close()
        ElseIf status = "เจ้าของร้าน" Then
            sb.Remove(0, sb.Length())
            sb.Append("SELECT User_Name,User_Password FROM tb_User")
            sb.Append(" WHERE (User_Name=@User_Name)")
            sb.Append(" AND (User_Password=@User_Password)")

            sqlLogin = sb.ToString()
            com = New SqlCommand()
            With com
                .CommandText = sqlLogin
                .CommandType = CommandType.Text
                .Connection = Conn
                .Parameters.Clear()
                .Parameters.Add("@User_Name", SqlDbType.VarChar).Value = txtUserName.Text
                .Parameters.Add("@User_Password", SqlDbType.VarChar).Value = txtPassword.Text
                dr = .ExecuteReader()
                If dr.HasRows Then
                    str = "1"
                    fromMainn.Show()
                    Me.Hide()
                Else
                    MessageBox.Show("UserName หรือ Password ที่คุณป้อน ไม่ถูกต้อง !!!", "ผลการทำงาน", MessageBoxButtons.OK, MessageBoxIcon.Exclamation)
                End If
            End With
            dr.Close()
        End If
    End Sub
    Private Sub btnLogin_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnLogin.Click
        Login()
    End Sub

    Private Sub btnExit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnExit.Click
        Application.Exit()
        Me.Close()
    End Sub
End Class