Form Object (Access)

A Form object refers to a particular Microsoft Access form.

Remarks

A Form object is a member of the Forms collection, which is a collection of all currently open forms. Within the Forms collection, individual forms are indexed beginning with zero. You can refer to an individual Form object in the Forms collection either by referring to the form by name, or by referring to its index within the collection. If you want to refer to a specific form in the Forms collection, it's better to refer to the form by name because a form's collection index may change. If the form name includes a space, the name must be surrounded by brackets ([ ]).

Each Form object has a Controls collection, which contains all controls on the form. You can refer to a control on a form either by implicitly or explicitly referring to the Controls collection. Your code will be faster if you refer to the Controls collection implicitly. The following examples show two of the ways you might refer to a control named NewData on the form called OrderForm:

' Implicit reference. 
Forms!OrderForm!NewData

' Explicit reference. 
Forms!OrderForm.Controls!NewData

The next two examples show how you might refer to a control named NewData on a subform ctlSubForm contained in the form called OrderForm:

Forms!OrderForm.ctlSubForm.Form!Controls.NewData

Forms!OrderForm.ctlSubForm!NewData

Links provided by: Luke Chung, FMS, Inc. | About the Contributors

• Microsoft Access Form Tips and Avoiding Common Mistakes

• Microsoft Office Access 2007 Form Design Tips

Links provided by: The UtterAccess community | About the Contributors

• Display Pictures on a Form

• Display Related Data

• Opening a Detail Form to Related Information

• Forms: Populate Controls/Text Boxes Based on Combobox Selection

• Referring To Properties And Controls On Subforms

Example

The following example shows how to use TextBox controls to supply date criteria for a query.

UtterAccess members can download a database that contains this example from here.

Sample code provided by: The UtterAccess community | About the Contributors

Private Sub cmdSearch_Click()

   Dim db As DAO.Database
   Dim qd As QueryDef
   Dim vWhere As Variant

   Set db = CurrentDb()

   On Error Resume Next
   db.QueryDefs.Delete "Query1"
   On Error GoTo 0

   vWhere = Null

   vWhere = vWhere & " AND [PayeeID]=" + Me.cboPayeeID

   If Nz(Me.txtEndDate, "") <> "" And Nz(Me.txtStartDate, "") <> "" Then
      vWhere = vWhere & " AND [RefundProcessed] Between #" & _
      Me.txtStartDate & "# AND #" & Me.txtEndDate & "#"
   Else
      If Nz(Me.txtEndDate, "") = "" And Nz(Me.txtStartDate, "") <> "" Then
         vWhere = vWhere & " AND [RefundProcessed]>=#" _
                  + Me.txtStartDate & "#"
      Else
         If Nz(Me.txtEndDate, "") <> "" And Nz(Me.txtStartDate, "") = "" Then
            vWhere = vWhere & " AND [RefundProcessed] <=#" _
                     + Me.txtEndDate & "#"
      End If
     End If
   End If

   If Nz(vWhere, "") = "" Then
      MsgBox "There are no search criteria selected." & vbCrLf & vbCrLf & _
             "Search Cancelled.", vbInformation, "Search Canceled."
   Else
      Set qd = db.CreateQueryDef("Query1", "SELECT * FROM tblRefundData” & _
               " WHERE " & Mid(vWhere, 6))
      db.Close
      Set db = Nothing

      DoCmd.OpenQuery "Query1", acViewNormal, acReadOnly
   End If
End Sub

The following example shows how to use the BeforeUpdate event of a form to require that a value be entered into one control when another control also has data.

Sample code provided by: The Microsoft Access 2010 Programmer’s Reference | About the Contributors

Private Sub Form_BeforeUpdate(Cancel As Integer)
If (IsNull(Me.FieldOne)) Or (Me.FieldOne.Value =  "") Then
    ' No action required
Else
    If (IsNull(Me.FieldTwo)) or (Me.FieldTwo.Value = "") Then
        MsgBox "You must provide data for field 'FieldTwo', " & _
            "if a value is entered in FieldOne", _
            vbOKOnly, "Required Field"
        Me.FieldTwo.SetFocus
        Cancel = True
        Exit Sub
    End If
End If

End Sub

The following example shows how to use the OpenArgs property to prevent a form from being opened from the Navigation Pane.

Private Sub Form_Open(Cancel As Integer)

If Me.OpenArgs() <> "Valid User" Then
    MsgBox "You are not authorized to use this form!", _
        vbExclamation + vbOKOnly, "Invalid Access"
    Cancel = True
End If
End Sub

The following example shows how to use the WhereCondition argument of the OpenForm method to filter the records displayed on a form as it is opened.

Private Sub cmdShowOrders_Click()
If Not Me.NewRecord Then
    DoCmd.OpenForm "frmOrder", _
        WhereCondition:="CustomerID=" & Me.txtCustomerID
End If
End Sub

About the Contributors

Luke Chung은 유명한 사용자 지정 데이터베이스 솔루션 및 개발자 도구 공급업체인 FMS, Inc.(영문일 수 있음)의 설립자이자 사장입니다.

UtterAccess(영문일 수 있음)는 Microsoft Access 위키 및 도움말 포럼입니다. 가입하려면 여기를 클릭하십시오(영문일 수 있음).

Wrox Press(영문일 수 있음)는 프로그래머가 프로그래머를 위해 집필한 서적을 전문으로 출판하는 업체로, 이러한 서적에서는 실제 프로그래밍 관련 문제에 대한 신뢰할 수 있는 해결 방법을 제공합니다.

참고 항목

개념

Access Object Model Reference

Form Object Members