Visual Basic

Option Explicit
Declare Function SetWindowsHookEx Lib "user32" Alias "SetWindowsHookExA" (ByVal idHook As Long, ByVal lpfn As Long, ByVal hmod As Long, ByVal dwThreadId As Long) As Long
Declare Function UnhookWindowsHookEx Lib "user32" (ByVal hHook As Long) As Long
Declare Function CallNextHookEx Lib "user32" (ByVal hHook As Long, ByVal ncode As Long, ByVal wParam As Long, lParam As Any) As Long

Public hnexthookproc As Long
'Public Const HC_ACTION = 0
'Public Const WH_KEYBOARD = 2

Public Sub UnHookKBD()

    If hnexthookproc <> 0 Then
        UnhookWindowsHookEx hnexthookpro
        hnexthookproc = 0
    End If

End Sub

Public Function EnableKBDHook()

    If hnexthookproc <> 0 Then
        Exit Function
    End If

    hnexthookproc = SetWindowsHookEx(2, AddressOf MyKBHFunc, App.hInstance, 0)

    If hnexthookproc <> 0 Then
        EnableKBDHook = hnexthookproc
    End If

End Function

Private Sub Command1_Click()

    EnableKBDHook

End Sub

Private Sub Command2_Click()

    UnHookKBD

End Sub

Public Function MyKBHFunc(ByVal iCode As Long, ByVal wParam As Long, ByVal lParam As Long) As Long

    MyKBHFunc = 0
    If iCode < 0 Then
    MyKBHFunc = CallNextHookEx(hnexthookproc, iCode, wParam, lParam)
    Exit Function
    End If

    If wParam = vbKeyReturn Then

    Debug.Print "haha"
    Else
    Call CallNextHookEx(hnexthookproc, iCode, wParam, lParam)
    End If

End Function

Private Sub Form_Load()

    EnableKBDHook

End Sub

Private Sub Form_Unload(Cancel As Integer)

    CallUnHookKBD

End Sub

<br />
Private Sub txtCardNum_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles txtCardNum.KeyPress<br />
        If Char.IsNumber(e.KeyChar) Or e.KeyChar = Chr(13) Or e.KeyChar = Chr(8) Then<br />
            e.Handled = False<br />
            If e.KeyChar = Chr(13) Then<br />
                If txtCardNum.Text = "" Then<br />
                    MsgBox("User ID can not be empty")<br />
                Else<br />
                    Dim CardNum As String = txtCardNum.Text<br />
                    <br />
                    Dim SQL As String<br />
                    SQL = "SELECT U.CodUser, U.FullName FROM tblUser U INNER JOIN tblAccess A ON U.CodUser = A.CodUser WHERE A.AccessLevel = 'Admin' AND A.CodUser = @CodUser"<br />
                    Dim myCommand = New SqlCommand(SQL, myConnection)<br />
                    myCommand.Parameters.Add("@CodUser", SqlDbType.VarChar).Value = CardNum<br />
<br />
                    Dim SQL2 As String<br />
                    SQL2 = "SELECT CodUser, FullName FROM tblUser WHERE CodUser = @CodUser"<br />
                    Dim myCommand2 = New SqlCommand(SQL2, myConnection)<br />
                    myCommand2.Parameters.Add("@CodUser", SqlDbType.VarChar).Value = CardNum<br />
<br />
                    Dim reader As SqlDataReader = myCommand.ExecuteReader()<br />
                    Dim reader2 As SqlDataReader = myCommand2.ExecuteReader()<br />
                    'Caso existam linhas<br />
                    If reader.HasRows Then<br />
                        While reader.Read()<br />
                            lblFullName.Text = reader(1)<br />
                            lblLevel.Text = "Admin" <br />
                            txtCardNum.Text = ""                        <br />
                        End While<br />
                        reader.Close()<br />
                    Else<br />
                        Dim reader2 As SqlDataReader = myCommand2.ExecuteReader()<br />
                        lblNomeCliente.Text = reader2(1)<br />
                        lblLevel.Text = "Normal User"<br />
                        txtCardNum.Text = ""<br />
                        reader2.Close()<br />
                    End If<br />
                End If<br />
            End If<br />
        Else<br />
            e.Handled = True<br />
        End If<br />
<br />
    End Sub<br />
<br />