Visual Basic 4 Database How-To/Visual Basic 4 Database - How-to (The Waite Group)(1995).iso/undobnd.fr_/undobnd.fr

Text File | 1995-07-04 | 5KB | 179 lines

VERSION 4.00
Begin VB.Form Form1
   BackColor       =   &H00C0C0C0&
   Caption         =   "Undo Browser"
   ClientHeight    =   2745
   ClientLeft      =   1155
   ClientTop       =   2295
   ClientWidth     =   6420
   BeginProperty Font
      name            =   "MS Sans Serif"
      charset         =   0
      weight          =   700
      size            =   8.25
      underline       =   0   'False
      italic          =   0   'False
      strikethrough   =   0   'False
   EndProperty
   Height          =   3435
   Left            =   1095
   LinkTopic       =   "Form1"
   ScaleHeight     =   2745
   ScaleWidth      =   6420
   Top             =   1665
   Width           =   6540
   Begin VB.TextBox txtISBN
      DataField       =   "ISBN"
      DataSource      =   "dtaTitles"
      Height          =   315
      Left            =   1860
      MaxLength       =   13
      TabIndex        =   2
      Top             =   1380
      Width           =   1635
   End
   Begin VB.TextBox txtYearPublished
      DataField       =   "Year Published"
      DataSource      =   "dtaTitles"
      Height          =   285
      Left            =   1860
      TabIndex        =   1
      Top             =   900
      Width           =   735
   End
   Begin VB.TextBox txtTitle
      DataField       =   "Title"
      DataSource      =   "dtaTitles"
      Height          =   555
      Left            =   1860
      MultiLine       =   -1  'True
      TabIndex        =   0
      Top             =   180
      Width           =   4095
   End
   Begin VB.Data dtaTitles
      Caption         =   "Titles"
      Connect         =   "Access"
      DatabaseName    =   "C:\VB\BIBLIO.MDB"
      Exclusive       =   0   'False
      Height          =   300
      Left            =   660
      Options         =   0
      ReadOnly        =   0   'False
      RecordsetType   =   1  'Dynaset
      RecordSource    =   "Titles"
      Top             =   2040
      Width           =   1815
   End
   Begin VB.Label Label3
      AutoSize        =   -1  'True
      BackColor       =   &H00C0C0C0&
      Caption         =   "ISBN:"
      Height          =   195
      Left            =   1200
      TabIndex        =   5
      Top             =   1440
      Width           =   510
   End
   Begin VB.Label Label2
      AutoSize        =   -1  'True
      BackColor       =   &H00C0C0C0&
      Caption         =   "Year Published:"
      Height          =   195
      Left            =   360
      TabIndex        =   4
      Top             =   960
      Width           =   1350
   End
   Begin VB.Label Label1
      AutoSize        =   -1  'True
      BackColor       =   &H00C0C0C0&
      Caption         =   "Title:"
      Height          =   195
      Left            =   1200
      TabIndex        =   3
      Top             =   180
      Width           =   450
   End
   Begin VB.Menu mnuFile
      Caption         =   "&File"
      Begin VB.Menu mnuFileExit
         Caption         =   "E&xit"
      End
   End
   Begin VB.Menu mnuEdit
      Caption         =   "&Edit"
      Begin VB.Menu mnuEditUndo
         Caption         =   "&Undo"
         Shortcut        =   %{BKSP}
      End
   End
End
Attribute VB_Name = "Form1"
Attribute VB_Creatable = False
Attribute VB_Exposed = False
Option Explicit

Private UpdateCancelled As Boolean

Private Sub dtaTitles_Validate(Action As Integer, Save As Integer)
    Dim msg As String

    If Save = True Then

        ' One or more bound controls has changed, so verify that all fields
        ' have legal entries. If a field has an incorrect value, set the
        ' variable msg to a string explaining the error and set the focus
        ' to that field to facilitate the user's correcting the error.
        If txtTitle = "" Then
             msg = "You must enter a title."
             txtTitle.SetFocus
        ElseIf txtISBN = "" Then
             msg = "You must enter an ISBN."
             txtISBN.SetFocus
        ElseIf txtYearPublished <> "" And Not IsNumeric(txtYearPublished) Then
            msg = "The Year Published must be numeric."
            txtYearPublished.SetFocus
        End If
    End If
    If msg <> "" Then

        ' We have something in the variable msg, which means that an error
        ' has occurred. Display the message for the user.
        MsgBox msg, vbExclamation

                ' Cancel the Validate event
        Action = vbDataActionCancel

        ' Set the form-level variable UpdateCancelled to True. This flags
        ' the Unload event to cancel the unload.
        UpdateCancelled = True

    Else

        ' No errors, so set the form level variable UpdateCancelled False
        ' to flag the Unload event to go ahead and proceed with the unload.
        UpdateCancelled = False
    End If

End Sub

Private Sub mnuEditUndo_Click()

    ' The user wants to undo all changes to the current record, so restore
    ' the values in the controls to the recordset values.
    dtaTitles.UpdateControls
End Sub

Private Sub mnuFileExit_Click()
   Unload Me
End Sub

Private Sub Form_Unload(Cancel As Integer)
    ' If the Validate event set the UpdateCancelled flag, cancel the unload.
    If UpdateCancelled Then Cancel = True
End Sub