Properties Collection

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Access Developer Reference

A Properties collection contains all the Property objects for a specific instance of an object.

Remarks

Every DAO object except the Connection and Error objects contains a Properties collection, which has certain built-in Property objects. These Property objects (which are often just called properties) uniquely characterize that instance of the object.

In addition to the built-in properties, you can also create and add your own user-defined properties. To add a user-defined property to an existing instance of an object, first define its characteristics with the CreateProperty method, then add it to the collection with the Append method. Referencing a user-defined Property object that has not yet been appended to a Properties collection will cause an error, as will appending a user-defined Property object to a Properties collection containing a Property object of the same name.

You can use the Delete method to remove user-defined properties from the Properties collection, but you can't remove built-in properties.

Bb177470.vs_note(en-us,office.12).gif  Note
A user-defined Property object is associated only with the specific instance of an object. The property isn't defined for all instances of objects of the selected type.

To refer to a built-in Property object in a collection by its ordinal number or by its Name property setting, use any of the following syntax forms:

object.Properties(0)

object.Properties("name")

object.Properties![name]

For a built-in property, you can also use this syntax:

object.name

Bb177470.vs_note(en-us,office.12).gif  Note
For a user-defined property, you must use the full object.Properties("name") syntax.

With the same syntax forms, you can also refer to the Value property of a Property object. The context of the reference will determine whether you are referring to the Property object itself or the Value property of the Property object.

Example

This example creates a user-defined property for the current database, sets its Type and Value properties, and appends it to the Properties collection of the database. Then the example enumerates all properties in the database.

Visual Basic for Applications 
  Sub PropertyX()

Dim dbsNorthwind As Database
Dim prpNew As Property
Dim prpLoop As Property


Set dbsNorthwind = OpenDatabase("Northwind.mdb")


With dbsNorthwind
' Create and append user-defined property.
Set prpNew = .CreateProperty()
prpNew.Name = "UserDefined"
prpNew.Type = dbText
prpNew.Value = "This is a user-defined property."
.Properties.Append prpNew


  ' Enumerate all properties of current database.
  Debug.Print "Properties of " & .Name
  For Each prpLoop In .Properties
     With prpLoop
        Debug.Print "  " & .Name
        Debug.Print "    Type: " & .Type
        Debug.Print "    Value: " & .Value
        Debug.Print "    Inherited: " & _
           .Inherited
     End With
  Next prpLoop

  ' Delete new property because this is a 
  ' demonstration.
  .Properties.Delete "UserDefined"



End With


End Sub

This example tries to set the value of a user-defined property. If the property doesn't exist, it uses the CreateProperty method to create and set the value of the new property. The SetProperty procedure is required for this procedure to run.

Visual Basic for Applications 
  Sub CreatePropertyX()

Dim dbsNorthwind As Database
Dim prpLoop As Property


Set dbsNorthwind = OpenDatabase("Northwind.mdb")


' Set the Archive property to True.
SetProperty dbsNorthwind, "Archive", True


With dbsNorthwind
Debug.Print "Properties of " & .Name


  ' Enumerate Properties collection of the Northwind 
  ' database.
  For Each prpLoop In .Properties
     If prpLoop <> "" Then Debug.Print "  " & _
        prpLoop.Name & " = " & prpLoop
  Next prpLoop

  ' Delete the new property since this is a 
  ' demonstration.
  .Properties.Delete "Archive"

  .Close



End With


End Sub


Sub SetProperty(dbsTemp As Database, strName As String, _
booTemp As Boolean)


Dim prpNew As Property
Dim errLoop As Error


' Attempt to set the specified property.
On Error GoTo Err_Property
dbsTemp.Properties("strName") = booTemp
On Error GoTo 0


Exit Sub


Err_Property:


' Error 3270 means that the property was not found.
If DBEngine.Errors(0).Number = 3270 Then
' Create property, set its value, and append it to the
' Properties collection.
Set prpNew = dbsTemp.CreateProperty(strName, _
dbBoolean, booTemp)
dbsTemp.Properties.Append prpNew
Resume Next
Else
' If different error has occurred, display message.
For Each errLoop In DBEngine.Errors
MsgBox "Error number: " & errLoop.Number & vbCr & _
errLoop.Description
Next errLoop
End
End If


End Sub

See Also