ไม่สามารถเชื่่อมต่อกับ SQL เข้ากับ VB ได้ผู้รู้ช่วยตอบวิธีการแก้ไขปัญหาหน่อยครับ

Imports System
Imports System.Collections.Generic
Imports System.ComponentModel
Imports System.Data
Imports System.Drawing
Imports System.Linq
Imports System.Text
Imports System.Windows.Forms
Imports System.Collections
Imports System.Data.SqlClient
Imports System.Data.OleDb
Imports System.IO

Public Class BS_Login
    'Private Con As SqlConnection
    'Private sql As String
    'Private command As SqlCommand
    Private Adapter As SqlDataAdapter
    'Private data As DataSet
    'Private BindingSrc As BindingSource
    Private sb As StringBuilder
    Private Conn As SqlConnection
    Private com As SqlCommand
    Private dr As SqlDataReader

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

        Dim strConn As String
        strConn = "Provider=SQLOLEDB; " & _
                    "Data Source=PC2011110713SUS\SQL; " & _
                    "Initial Catalog=BookShop_DB; " & _
                    "UID=sa; " & _
                    "Password=1234;"
        If (Conn.State = ConnectionState.Open) Then
            Conn.Close()
        End If
        Conn.ConnectionString = strConn
        Conn.Open()

        sb.Append("select username,password from bs_em ")
        sb.Append(" where username = '" + TextBox1.Text.Trim + "' ")
        sb.Append(" and password = '" + TextBox2.Text.Trim + "' ")

        Dim sqlLogin
        sqlLogin = sb.ToString

        com.CommandType = CommandType.Text
        com.CommandText = sqlLogin
        com.Connection = Conn

        dr = com.ExecuteReader
        If (dr.HasRows) Then
            dr.Read()

            Dim mian = New BS_Mian
            Dim log = New BS_Login
            mian.Show()
            log.Hide()
        Else
            MessageBox.Show("คุณกรอก Username หรือ Password ไม่ถูกต้อง", "แจ้งเตือน", MessageBoxButtons.OK, MessageBoxIcon.Error)
            cler()
            TextBox1.Focus()
        End If
    End Sub

  
End Class

Private Conn As New SqlConnection