TDABaseField

Overview

TDABaseField is a class that provides access to Value via different getters/setters like AsString, AsByte etc.

Location

 

constructor Create  override

Creates a new instance.

constructor Create(Collection: TCollection)

Parameters:

  • Collection: collection which the field belongs to

AsAnsiString

Gets or sets the value of the field as 8-bit ANSI string value.

property AsAnsiString: string read write

AsBlob

Gets or sets the value of the field as Blob value.

property AsBlob: TBlobData read write

AsBoolean

Gets or sets the value of the field as Boolean value.

property AsBoolean: boolean read write

AsByte

Gets or sets the value of the field as Byte value.

property AsByte: Byte read write

AsBytes

Gets or sets the value of the field as Bytes value.

property AsBytes: TBytes read write

AsCardinal

Gets or sets the value of the field as Cardinal value.

property AsCardinal: Cardinal read write

AsCurrency

Gets or sets the value of the field as 64-bit fixed point Currency value.

property AsCurrency: currency read write

AsDateTime

Gets or sets the value of the field as TDateTime value.

property AsDateTime: TDateTime read write

AsDecimal

Gets or sets the value of the field as binary coded decimal value.

property AsDecimal: TBcd read write

AsFloat

Gets or sets the value of the field as Float/Double value.

property AsFloat: double read write

AsGuid

Gets or sets the value of the field as TGUID value.

property AsGuid: TGUID read write

AsInteger

Gets or sets the value of the field as 32-bit integer value.

property AsInteger: integer read write

AsLargeInt

Gets or sets the value of the field as 64-bit integer value.

property AsLargeInt: Int64 read write

AsLargeUInt

Gets or sets the value of the field as 64-bit unsigned integer value.

property AsLargeUInt: UInt64 read write

AsShortInt

Gets or sets the value of the field as ShortInt value.

property AsShortInt: ShortInt read write

Assign  override

Assigns the Source field.

procedure Assign(Source: TPersistent)

Parameters:

  • Source: Instance whose properties will be copied

AssignField  virtual

Assigns the Source field

procedure AssignField(Source: TDABaseField)

Parameters:

  • Source: TDABaseField instance that current TDABaseField should be assigned to

AsSingle

Gets or sets the value of the field as Single value.

property AsSingle: Single read write

AsSmallInt

Gets or sets the value of the field as SmallInt value.

property AsSmallInt: SmallInt read write

AsString

Gets or sets the value of the field as string value.

property AsString: string read write

AsVariant

Gets or sets the value of the field as variant.

property AsVariant: variant read write

AsWideString

Gets or sets the value of the field as 16-bit Unicode WideString value.

property AsWideString: UnicodeString read write

AsWord

Gets or sets the value of the field as Word value.

property AsWord: Word read write

AsXml

Gets or sets the value of the field as XML node.

property AsXml: IXMLNode read write

BlobSize

Indicates the number of bytes of data contained in the blob field on the current record.

property BlobSize: Integer read write

BlobType

Manages additional Blob options, if the DataType of the field is set to datBlob.

property BlobType: TDABlobType read write

Clear

Clears the value of the field by setting it to Null.

procedure Clear

DataType

Specifies the type of data contained within the field, from a collection of supported TDADataTypes. Depending on the data type, the Size and BlobType properties are also used to further define the data type in more detail. For datString and datWideString, Size will define the maximum length of string permitted for the field; for blobs and memos, BlobType provides special options.

property DataType: TDADataType read write

DecimalPrecision

Specifies decimal precision for a binary coded decimal value (if the DataType of the field is set to datDecimal).

property DecimalPrecision: Integer read write

DecimalScale

Specifies decimal scale for a binary coded decimal value (if the DataType of the field is set to datDecimal).

property DecimalScale: Integer read write

Description

Provides a human-readable description of the field. This property will not be used by the Data Abstract library, but can be filled with description text for documentation purposes when defining the field or parameter in Schema Modeler.

property Description: string read write

DictionaryEntry

Name of the data dictionary for the field

property DictionaryEntry: string read write

GeneratorName

For fields of type datAutoInc, this property specifies the name of the generator in the back-end database that will be used to generate new primary key values. This applies only to database types that do not natively support AutoInc fields (such as Oracle or Interbase). Please refer to the AutoIncs and Generators help topic for more detail.

property GeneratorName: string read write

GetDisplayName  protected override

Returns Name of the field

function GetDisplayName: string

GetIsNull  protected virtual

Returns whether the field currently contains a value (false) or is Null (true).

function GetIsNull: boolean

GetNamePath  override

Returns the name of the object as it appears in the Object Inspector

function GetNamePath: string

HasValidDictionaryField  virtual

Indicates if the field has appropriate data dictionary entry

function HasValidDictionaryField: Boolean

IsCompatibleV4  protected virtual

Indicates if the field is compatible with DA v.4 . Returns False

function IsCompatibleV4: boolean

IsNull

Returns whether the field currently contains a value (false) or is Null (true).

property IsNull: boolean read write

MergeDatadictionaries  protected virtual

One of the conditions for indicating if the field's property should be saved on the form or when TDASchema is saved. For internal using.

function MergeDatadictionaries: Boolean

Name

Defines the name of the field or parameter. This name usually matches the name of the underlying field in the physical database, or it's mapped to a different field using the data tables column mapping.

property Name: string read write

QueryInterface  protected stdcall    (declared in TInterfacedCollectionItem)

Returns a reference to a specified interface if the object supports that interface. This is one of the methods introduced by the IUnknown interface.

function QueryInterface(const IID: TGUID; out Obj: ): HResult

Parameters:

  • IID: Identifier of the interface to return
  • Obj: Variable to store the returned interface reference to

SetDisplayName  protected override

Sets the name of the field as it appears in the collection editor.

procedure SetDisplayName(const Value: string)

Parameters:

  • Value: value for the Name property

Size

Sets the maximum length of string permitted for the field, DataType is set to datString or datWideString.

property Size: integer read write

StoreBlobType  protected

Indicates if original field's BlobType property (not appropriate data dictionary property) should be saved in the form file or when saving TDASchema. Not used for now

function StoreBlobType: boolean

StoreDataType  protected

Indicates if field's DataType property (not appropriate data dictionary property) should be saved in the form file or when saving TDASchema. Not used for now.

function StoreDataType: Boolean

StoreDecimalPrecision  protected

Indicates if field's DecimalPrecision property (not appropriate data dictionary property) should be saved in the form file or when saving TDASchema.

function StoreDecimalPrecision: Boolean

StoreDecimalScale  protected

Indicates if field's DecimalScale property (not appropriate data dictionary property) should be saved in the form file or when saving TDASchema.

function StoreDecimalScale: Boolean

StoreDescription  protected

Indicates if field's DecimalPrecision property (not appropriate data dictionary property) should be saved in the form file or when saving TDASchema. Not used for now

function StoreDescription: Boolean

StoreGeneratorName  protected

Indicates if field's DecimalPrecision property (not appropriate data dictionary property) should be saved in the form file or when saving TDASchema. Not used for now

function StoreGeneratorName: Boolean

StoreSize  protected

Indicates if field's DecimalPrecision property (not appropriate data dictionary property) should be saved in the form file or when saving TDASchema. Not used for now

function StoreSize: Boolean

Tag

Tag has no predefined meaning. The Tag property can store any additional integer value for the convenience of developers

property Tag: integer read write

Value

Gets or sets the value of the field as variant.

property Value: Variant read write

 

AsAnsiString

Gets or sets the value of the field as 8-bit ANSI string value.

property AsAnsiString: string read write

AsBlob

Gets or sets the value of the field as Blob value.

property AsBlob: TBlobData read write

AsBoolean

Gets or sets the value of the field as Boolean value.

property AsBoolean: boolean read write

AsByte

Gets or sets the value of the field as Byte value.

property AsByte: Byte read write

AsBytes

Gets or sets the value of the field as Bytes value.

property AsBytes: TBytes read write

AsCardinal

Gets or sets the value of the field as Cardinal value.

property AsCardinal: Cardinal read write

AsCurrency

Gets or sets the value of the field as 64-bit fixed point Currency value.

property AsCurrency: currency read write

AsDateTime

Gets or sets the value of the field as TDateTime value.

property AsDateTime: TDateTime read write

AsDecimal

Gets or sets the value of the field as binary coded decimal value.

property AsDecimal: TBcd read write

AsFloat

Gets or sets the value of the field as Float/Double value.

property AsFloat: double read write

AsGuid

Gets or sets the value of the field as TGUID value.

property AsGuid: TGUID read write

AsInteger

Gets or sets the value of the field as 32-bit integer value.

property AsInteger: integer read write

AsLargeInt

Gets or sets the value of the field as 64-bit integer value.

property AsLargeInt: Int64 read write

AsLargeUInt

Gets or sets the value of the field as 64-bit unsigned integer value.

property AsLargeUInt: UInt64 read write

AsShortInt

Gets or sets the value of the field as ShortInt value.

property AsShortInt: ShortInt read write

AsSingle

Gets or sets the value of the field as Single value.

property AsSingle: Single read write

AsSmallInt

Gets or sets the value of the field as SmallInt value.

property AsSmallInt: SmallInt read write

AsString

Gets or sets the value of the field as string value.

property AsString: string read write

AsVariant

Gets or sets the value of the field as variant.

property AsVariant: variant read write

AsWideString

Gets or sets the value of the field as 16-bit Unicode WideString value.

property AsWideString: UnicodeString read write

AsWord

Gets or sets the value of the field as Word value.

property AsWord: Word read write

AsXml

Gets or sets the value of the field as XML node.

property AsXml: IXMLNode read write

BlobSize

Indicates the number of bytes of data contained in the blob field on the current record.

property BlobSize: Integer read write

BlobType

Manages additional Blob options, if the DataType of the field is set to datBlob.

property BlobType: TDABlobType read write

DataType

Specifies the type of data contained within the field, from a collection of supported TDADataTypes. Depending on the data type, the Size and BlobType properties are also used to further define the data type in more detail. For datString and datWideString, Size will define the maximum length of string permitted for the field; for blobs and memos, BlobType provides special options.

property DataType: TDADataType read write

DecimalPrecision

Specifies decimal precision for a binary coded decimal value (if the DataType of the field is set to datDecimal).

property DecimalPrecision: Integer read write

DecimalScale

Specifies decimal scale for a binary coded decimal value (if the DataType of the field is set to datDecimal).

property DecimalScale: Integer read write

Description

Provides a human-readable description of the field. This property will not be used by the Data Abstract library, but can be filled with description text for documentation purposes when defining the field or parameter in Schema Modeler.

property Description: string read write

DictionaryEntry

Name of the data dictionary for the field

property DictionaryEntry: string read write

GeneratorName

For fields of type datAutoInc, this property specifies the name of the generator in the back-end database that will be used to generate new primary key values. This applies only to database types that do not natively support AutoInc fields (such as Oracle or Interbase). Please refer to the AutoIncs and Generators help topic for more detail.

property GeneratorName: string read write

IsNull

Returns whether the field currently contains a value (false) or is Null (true).

property IsNull: boolean read write

Name

Defines the name of the field or parameter. This name usually matches the name of the underlying field in the physical database, or it's mapped to a different field using the data tables column mapping.

property Name: string read write

Size

Sets the maximum length of string permitted for the field, DataType is set to datString or datWideString.

property Size: integer read write

Tag

Tag has no predefined meaning. The Tag property can store any additional integer value for the convenience of developers

property Tag: integer read write

Value

Gets or sets the value of the field as variant.

property Value: Variant read write

 

constructor Create  override

Creates a new instance.

constructor Create(Collection: TCollection)

Parameters:

  • Collection: collection which the field belongs to

Assign  override

Assigns the Source field.

procedure Assign(Source: TPersistent)

Parameters:

  • Source: Instance whose properties will be copied

AssignField  virtual

Assigns the Source field

procedure AssignField(Source: TDABaseField)

Parameters:

  • Source: TDABaseField instance that current TDABaseField should be assigned to

Clear

Clears the value of the field by setting it to Null.

procedure Clear

GetDisplayName  protected override

Returns Name of the field

function GetDisplayName: string

GetIsNull  protected virtual

Returns whether the field currently contains a value (false) or is Null (true).

function GetIsNull: boolean

GetNamePath  override

Returns the name of the object as it appears in the Object Inspector

function GetNamePath: string

HasValidDictionaryField  virtual

Indicates if the field has appropriate data dictionary entry

function HasValidDictionaryField: Boolean

IsCompatibleV4  protected virtual

Indicates if the field is compatible with DA v.4 . Returns False

function IsCompatibleV4: boolean

MergeDatadictionaries  protected virtual

One of the conditions for indicating if the field's property should be saved on the form or when TDASchema is saved. For internal using.

function MergeDatadictionaries: Boolean

QueryInterface  protected stdcall    (declared in TInterfacedCollectionItem)

Returns a reference to a specified interface if the object supports that interface. This is one of the methods introduced by the IUnknown interface.

function QueryInterface(const IID: TGUID; out Obj: ): HResult

Parameters:

  • IID: Identifier of the interface to return
  • Obj: Variable to store the returned interface reference to

SetDisplayName  protected override

Sets the name of the field as it appears in the collection editor.

procedure SetDisplayName(const Value: string)

Parameters:

  • Value: value for the Name property

StoreBlobType  protected

Indicates if original field's BlobType property (not appropriate data dictionary property) should be saved in the form file or when saving TDASchema. Not used for now

function StoreBlobType: boolean

StoreDataType  protected

Indicates if field's DataType property (not appropriate data dictionary property) should be saved in the form file or when saving TDASchema. Not used for now.

function StoreDataType: Boolean

StoreDecimalPrecision  protected

Indicates if field's DecimalPrecision property (not appropriate data dictionary property) should be saved in the form file or when saving TDASchema.

function StoreDecimalPrecision: Boolean

StoreDecimalScale  protected

Indicates if field's DecimalScale property (not appropriate data dictionary property) should be saved in the form file or when saving TDASchema.

function StoreDecimalScale: Boolean

StoreDescription  protected

Indicates if field's DecimalPrecision property (not appropriate data dictionary property) should be saved in the form file or when saving TDASchema. Not used for now

function StoreDescription: Boolean

StoreGeneratorName  protected

Indicates if field's DecimalPrecision property (not appropriate data dictionary property) should be saved in the form file or when saving TDASchema. Not used for now

function StoreGeneratorName: Boolean

StoreSize  protected

Indicates if field's DecimalPrecision property (not appropriate data dictionary property) should be saved in the form file or when saving TDASchema. Not used for now

function StoreSize: Boolean

Descendants

See Also