ผมต้องการเพิ่ม ฐานข้อมูล 2 ตาราง ใน Button เดียวจะทำได้ไหมครับ ... You must enter a value in the 'xxx' field.

Imports System.Data.OleDb
Imports System.Data
Public Class Form1
    Public conn As New OleDbConnection
    Public Sub connectData() Handles MyBase.Load
        Dim s As String
        If conn.State = ConnectionState.Open Then conn.Close()

        s = "Provider=Microsoft.ACE.OLEDB.12.0;"
        s = s + "Data Source=C:\Database.accdb;"
        s += "User Id = Admin;Password=;"

        conn.ConnectionString = s
        conn.Open()

    End Sub
    Public Function ExecuteSQL(ByVal prmSQL As String) As Boolean
        connectData()
        Dim addCom As New OleDbCommand
        With addCom
            .CommandType = CommandType.Text
            .CommandText = prmSQL
            .Connection = conn
            .ExecuteNonQuery()
        End With
        ExecuteSQL = True
    End Function

    Private Sub DateTimePicker1_ValueChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txtsell_date.ValueChanged

    End Sub

    Private Sub GroupBox1_Enter(ByVal sender As System.Object, ByVal e As System.EventArgs)

    End Sub

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs)

    End Sub

    Private Sub Form1_Load_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        connectData()
        MsgBox("เชื่อมต่อฐานข้อมูลสำเร็จ")
    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        'เพิ่มข้อมูลลงในตาราง Selling'
        Dim sql As String = "INSERT INTO selling(sell_no) VALUES " & "(@sell_no)"
        Dim cmd1 As New OleDbCommand(sql, conn)
        cmd1.Parameters.AddWithValue("@sell_no", txtsell_no.Text)
        cmd1.ExecuteNonQuery()

        'เพิ่มข้อมูลลงในตาราง Employee'
        Dim sql2 As String = "INSERT INTO employee(emp_id) VALUES " & "(@emp_id)"
        Dim cmd2 As New OleDbCommand(sql2, conn)
        cmd2.Parameters.AddWithValue("@emp_id", txtemp_id.Text)
        cmd2.ExecuteNonQuery()

        'Dim sql As String =
        'sql = "INSERT INTO selling(sell_no, sell_date)VALUES("
        'sql += "'" & txtsell_no.Text & "',"
        'sql += "'" & txtsell_date.Text & "'"
        'sql += ")"
        'sql = "INSERT INTO employee(emp_id)VALUES("
        'sql += "'" & txtemp_id.Text & "'"
        ' sql += ")"
        'sql = "INSERT INTO product(pro_id, pro_price, pro_name, pro_amount)VALUES("
        'sql += "'" & txtpro_id.Text & "',"
        'sql += "'" & txtpro_price.Text & "',"
        'sql += "'" & txtpro_name.Text & "',"
        'sql += "'" & txtpro_amount.Text & "'"
        'sql += ")"
        'ExecuteSQL(sql)
        MsgBox("บันทึกข้อมูลสำเร็จ")

    End Sub

    Private Sub txtsell_no_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txtsell_no.TextChanged

    End Sub
End Class