Field Object

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A Field object represents a column of data with a common data type and a common set of properties.

Remarks

The Fields collections of Index, QueryDef, Relation, and TableDef objects contain the specifications for the fields those objects represent. The Fields collection of a Recordset object represents the Field objects in a row of data, or in a record. You use the Field objects in a Recordset object to read and set values for the fields in the current record of the Recordset object.

In both Microsoft Jet and ODBCDirect workspaces, you manipulate a field using a Field object and its methods and properties. For example, you can:

• Use the OrdinalPosition property to set or return the presentation order of the Field object in a Fields collection. (This property is read-only for ODBCDirect databases.)
  
  
• Use the Value property of a field in a Recordset object to set or return stored data.
  
  
• Use the AppendChunk and GetChunk methods and the FieldSize property to get or set a value in an OLE Object or Memo field of a Recordset object.
  
  
• Use the Type, Size, and Attributes properties to determine the type of data that can be stored in the field.
  
  
• Use the SourceField and SourceTable properties to determine the original source of the data.

In Microsoft Jet workspaces, you can:

• Use the ForeignName property to set or return information about a foreign field in a Relation object.
  
  
• Use the AllowZeroLength, DefaultValue, Required, ValidateOnSet, ValidationRule, or ValidationText properties to set or return validation conditions.
  
  
• Use the DefaultValue property of a field on a TableDef object to set the default value for this field when new records are added.

In ODBCDirect workspaces, you can:

• Use the Value, VisibleValue, and OriginalValue properties to verify successful completion of a batch update.

Note For a complete list of all methods, properties, and collections available on a Field object in any database or connection, see the Summary topic.

To create a new Field object in an Index, TableDef, or Relation object, use the CreateField method.

When you access a Field object as part of a Recordset object, data from the current record is visible in the Field object's Value property. To manipulate data in the Recordset object, you don't usually reference the Fields collection directly; instead, you indirectly reference the Value property of the Field object in the Fields collection of the Recordset object.

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

Fields(0)

Fields("name")

Fields![name]

With the same syntax forms, you can also refer to the Value property of a Field object that you create and append to a Fields collection. The context of the field reference will determine whether you are referring to the Field object or the Value property of the Field object.