[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] Reference for unit 'DB' (#fcl)

TFieldDef

[Properties (by Name)] [Methods (by Name)] [Events (by Name)]

Class to describe one field in a record in a dataset

Declaration

Source position: db.pas line 165

type TFieldDef = class(TNamedItem)

public

  constructor Create();

  

Constructor for TFieldDef.

  destructor Destroy; override;

  

Free the TFieldDef instance

  procedure Assign(); override;

  

Assign the contents of one TFieldDef instance to another.

  function CreateField();

  

Create TField instance based on definitions in current TFieldDef instance.

  property FieldClass: TFieldClass; [r]

  

TField class used for this fielddef

  property FieldNo: LongInt; [r]

  

Field number

  property CharSize: Word; [r]

  

Character size

  property InternalCalcField: Boolean; [rw]

  

Is this a definition of an internally calculated field ?

  property Required: Boolean; [rw]

  

Is the field required ?

  property Codepage: TSystemCodePage; [r]

published

  property Attributes: TFieldAttributes; [rw]

  

Additional attributes of the field.

  property DataType: TFieldType; [rw]

  

Data type for the field

  property Precision: LongInt; [rw]

  

Precision used in BCD (Binary Coded Decimal) fields

  property Size: Integer; [rw]

  

Size of the buffer needed to store the data of the field

end;

Inheritance

TFieldDef

  

Class to describe one field in a record in a dataset

|

TNamedItem

  

Named collection item

|

TCollectionItem

|

TPersistent,IFPObserved

|

TObject

Description

TFieldDef is used to describe the fields that are present in the data underlying the dataset. For each field in the underlying field, an TFieldDef instance is created when the dataset is opened. This class offers almost no methods, it is mainly a storage class, to store all relevant properties of fields in a record (name, data type, size, required or not, etc.)

See also

TDataset.FieldDefs

  

Definitions of available fields in the underlying database

TFieldDefs

  

Collection of TFieldDef instances.


Documentation generated on: Jun 22 2020