Property Object (DAO)

Microsoft DAO 3.60

Property Object

                   

A Property object represents a built-in or user-defined characteristic of a DAO object.


Remarks

Every DAO object except the Connection and Error objects contains a Properties collection which has Property objects corresponding to built-in properties of that DAO object. The user can also define Property objects and append them to the Properties collection of some DAO objects. These Property objects (which are often just called properties) uniquely characterize that instance of the object.

You can create user-defined properties for the following objects:

  • Database, Index, QueryDef, and TableDef objects

  • Field objects in Fields collections of QueryDef and TableDef objects

To add a user-defined property, use the CreateProperty method to create a Property object with a unique Name property setting. Set the Type and Value properties of the new Property object, and then append it to the Properties collection of the appropriate object. The object to which you are adding the user-defined property must already be appended to a collection. 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 delete user-defined properties from the Properties collection, but you can't delete built-in properties.

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.

You can use the Properties collection of an object to enumerate the object's built-in and user-defined properties. You don't need to know beforehand exactly which properties exist or what their characteristics (Name and Type properties) are to manipulate them. However, if you try to read a write-only property, such as the Password property of a Workspace object, or try to read or write a property in an inappropriate context, such as the Value property setting of a Field object in the Fields collection of a TableDef object, an error occurs.

The Property object also has four built-in properties:

  • The Name property, a String that uniquely identifies the property.

  • The Type property, an Integer that specifies the property data type.

  • The Value property, a Variant that contains the property setting.

  • The Inherited property, a Boolean that indicates whether the property is inherited from another object. For example, a Field object in a Fields collection of a Recordset object can inherit properties from the underlying TableDef or QueryDef object.

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

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.