MORE INFORMATION
The
Form or
Report identifier is optional when referring to control properties. It
is necessary, however, when referring to subform or subreport
properties.
To refer to a control on a subform, use the following
syntax:
Forms![main form name]![subform control name].Form![control name]
To refer to a control on a subreport, use the following syntax:
Reports![main report name]![subreport control name].Report![control
name]
NOTE: Only subforms are discussed in the remainder of this article,
but all of the information in the article applies to both subforms and
subreports.
It is important to note that you cannot refer to controls
on a subform with the following syntax:
Forms![subform name]![control name]
This is because a subform on a main form is not a form, but is a
control just like a text box or a list box. You must refer to a subform as a
control rather than a form, and specify the Form identifier following the
subform control name reference to gain access to the controls on a
subform.
It is also important to note that when you are referring to
controls on a subform, you must specify the value contained in the
ControlName property of the subform control. The
ControlName property should not be confused with the
SourceObject property for a subform control. The
SourceObject property is used to indicate which subform to use in the subform
control. The
ControlName property is used to specify the name by which the subform control
is referenced. The
ControlName property is typically set the same as the
SourceObject property, but it does not have to be.
For example,
consider an Order Details subform on an Orders form with the following
properties:
Name: Order Details
Control Source: Order Details
You can refer to a Unit Price control on the Order Details
subform with the following reference:
Forms![Orders]![Order Details].Form![Unit Price]
If, however, the subform control has the following properties
Name: Details
Control Source: Order Details
you must refer to the Unit Price control on the Order Details
subform with this reference:
Forms![Orders]![Details].Form![Unit Price]
Examples of Referencing Controls on a Subform
You may use the following SetValue macro action to increase the
Unit Price value on the Orders subform by 10 percent:
Action: SetValue
Item: Forms![Orders]![Order Details].Form![Unit Price]
Expression: Forms![Orders]![Order Details].Form![Unit Price]* 1.1
If the macro is attached to a button on the Orders form, you can
use the following expression for the SetValue Expression argument:
Expression: [Order Details].Form![Unit Price]*1.1
If you are referring to a control on a subform from another
control on the same subform, you do not have to type the Form property
identifier. For example, to refer to the
Unit Price value on the Order Details subform in a macro attached to a
button on the Order Details subform, you can type:
The following expression can be entered as the
Control Source property for the
Subtotal control on the Orders main form to display a value calculated in
the hidden
Order Subtotal on the Order Details subform:
=[Orders Subform].Form![Order Subtotal]
To refer to the value of a control on the parent (main) form from
a control on a subform, use the
Parent property. For example, the following expression typed in a
control on a subform refers to the Customer ID field on the parent form:
To refer to a control on a nested subform (a subform on a
subform), you can use the following syntax:
Forms![main form name]![subform control name].Form![nested subform
control name].Form![control name]
Common Issues Encountered When Referencing Subform Controls