TDAParam

Overview

Descending from TDABaseField, TDAParam is used to represent an individual parameter for a command or data table.

Location

 

constructor Create  override    (declared in TDABaseField)

Creates a new instance.

constructor Create(Collection: TCollection)

Parameters:

  • Collection: collection which the field belongs to

AsAnsiString    (declared in TDABaseField)

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

property AsAnsiString: string read write

AsBlob    (declared in TDABaseField)

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

property AsBlob: TBlobData read write

AsBoolean    (declared in TDABaseField)

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

property AsBoolean: boolean read write

AsByte    (declared in TDABaseField)

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

property AsByte: Byte read write

AsBytes    (declared in TDABaseField)

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

property AsBytes: TBytes read write

AsCardinal    (declared in TDABaseField)

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

property AsCardinal: Cardinal read write

AsCurrency    (declared in TDABaseField)

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

property AsCurrency: currency read write

AsDateTime    (declared in TDABaseField)

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

property AsDateTime: TDateTime read write

AsDecimal    (declared in TDABaseField)

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

property AsDecimal: TBcd read write

AsFloat    (declared in TDABaseField)

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

property AsFloat: double read write

AsGuid    (declared in TDABaseField)

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

property AsGuid: TGUID read write

AsInteger    (declared in TDABaseField)

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

property AsInteger: integer read write

AsLargeInt    (declared in TDABaseField)

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

property AsLargeInt: Int64 read write

AsLargeUInt    (declared in TDABaseField)

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

property AsLargeUInt: UInt64 read write

AsShortInt    (declared in TDABaseField)

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

property AsShortInt: ShortInt read write

Assign  override    (declared in TDABaseField)

Assigns the Source field.

procedure Assign(Source: TPersistent)

Parameters:

  • Source: Instance whose properties will be copied

AssignField  override

Assigns the Source field

procedure AssignField(Source: TDABaseField)

Parameters:


AssignParam  virtual

Assigns the ParamType and other properties.

procedure AssignParam(Source: TDAParam)

Parameters:

  • Source: Instance whose properties will be copied

AsSingle    (declared in TDABaseField)

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

property AsSingle: Single read write

AsSmallInt    (declared in TDABaseField)

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:

AsVariant    (declared in TDABaseField)

Gets or sets the value of the field as variant.

property AsVariant: variant read write

AsWideString    (declared in TDABaseField)

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

property AsWideString: UnicodeString read write

AsWord    (declared in TDABaseField)

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

property AsWord: Word read write

AsXml    (declared in TDABaseField)

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

property AsXml: IXMLNode read write

BlobSize    (declared in TDABaseField)

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

property BlobSize: Integer read write

BlobType    (declared in TDABaseField)

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

property BlobType: TDABlobType read write

Clear    (declared in TDABaseField)

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

procedure Clear

DataType    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

Name of the data dictionary for the field

property DictionaryEntry: string read write

GeneratorName    (declared in TDABaseField)

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    (declared in TDABaseField)

Returns Name of the field

function GetDisplayName: string

GetIsNull  protected virtual    (declared in TDABaseField)

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

function GetIsNull: boolean

GetNamePath  override    (declared in TDABaseField)

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

function GetNamePath: string

HasValidDictionaryField  virtual    (declared in TDABaseField)

Indicates if the field has appropriate data dictionary entry

function HasValidDictionaryField: Boolean

IsCompatibleV4  protected virtual    (declared in TDABaseField)

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

function IsCompatibleV4: boolean

IsNull    (declared in TDABaseField)

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

property IsNull: boolean read write

LoadFromFile

Reads Value from file.

procedure LoadFromFile(const aFileName: string)

Parameters:

  • aFileName: given file name.

LoadFromStream

Reads Value from stream.

procedure LoadFromStream(const aStream: IROStream)

Parameters:

  • aStream: given stream.

MergeDatadictionaries  protected virtual    (declared in TDABaseField)

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    (declared in TDABaseField)

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

ParamType

Specifies the direction of the parameter. Command parameters can either be incoming (passed into the command), outgoing/result (returned from the command) or Incoming and Outgoing (both passed in and returned). Data table parameters can only be incoming.

property ParamType: TDAParamType 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

SaveToFile

Writes Value to file.

procedure SaveToFile(const aFileName: string)

Parameters:

  • aFileName: given file name.

SaveToStream

Writes Value to stream.

procedure SaveToStream(const aStream: IROStream)

Parameters:

  • aStream: given stream.

SetDisplayName  protected override    (declared in TDABaseField)

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    (declared in TDABaseField)

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

property Size: integer read write

StoreBlobType  protected    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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:

 

AsAnsiString    (declared in TDABaseField)

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

property AsAnsiString: string read write

AsBlob    (declared in TDABaseField)

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

property AsBlob: TBlobData read write

AsBoolean    (declared in TDABaseField)

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

property AsBoolean: boolean read write

AsByte    (declared in TDABaseField)

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

property AsByte: Byte read write

AsBytes    (declared in TDABaseField)

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

property AsBytes: TBytes read write

AsCardinal    (declared in TDABaseField)

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

property AsCardinal: Cardinal read write

AsCurrency    (declared in TDABaseField)

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

property AsCurrency: currency read write

AsDateTime    (declared in TDABaseField)

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

property AsDateTime: TDateTime read write

AsDecimal    (declared in TDABaseField)

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

property AsDecimal: TBcd read write

AsFloat    (declared in TDABaseField)

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

property AsFloat: double read write

AsGuid    (declared in TDABaseField)

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

property AsGuid: TGUID read write

AsInteger    (declared in TDABaseField)

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

property AsInteger: integer read write

AsLargeInt    (declared in TDABaseField)

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

property AsLargeInt: Int64 read write

AsLargeUInt    (declared in TDABaseField)

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

property AsLargeUInt: UInt64 read write

AsShortInt    (declared in TDABaseField)

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

property AsShortInt: ShortInt read write

AsSingle    (declared in TDABaseField)

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

property AsSingle: Single read write

AsSmallInt    (declared in TDABaseField)

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:

AsVariant    (declared in TDABaseField)

Gets or sets the value of the field as variant.

property AsVariant: variant read write

AsWideString    (declared in TDABaseField)

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

property AsWideString: UnicodeString read write

AsWord    (declared in TDABaseField)

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

property AsWord: Word read write

AsXml    (declared in TDABaseField)

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

property AsXml: IXMLNode read write

BlobSize    (declared in TDABaseField)

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

property BlobSize: Integer read write

BlobType    (declared in TDABaseField)

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

property BlobType: TDABlobType read write

DataType    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

Name of the data dictionary for the field

property DictionaryEntry: string read write

GeneratorName    (declared in TDABaseField)

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    (declared in TDABaseField)

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

property IsNull: boolean read write

Name    (declared in TDABaseField)

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

ParamType

Specifies the direction of the parameter. Command parameters can either be incoming (passed into the command), outgoing/result (returned from the command) or Incoming and Outgoing (both passed in and returned). Data table parameters can only be incoming.

property ParamType: TDAParamType read write

Size    (declared in TDABaseField)

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

property Size: integer read write

Tag    (declared in TDABaseField)

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:

 

constructor Create  override    (declared in TDABaseField)

Creates a new instance.

constructor Create(Collection: TCollection)

Parameters:

  • Collection: collection which the field belongs to

Assign  override    (declared in TDABaseField)

Assigns the Source field.

procedure Assign(Source: TPersistent)

Parameters:

  • Source: Instance whose properties will be copied

AssignField  override

Assigns the Source field

procedure AssignField(Source: TDABaseField)

Parameters:


AssignParam  virtual

Assigns the ParamType and other properties.

procedure AssignParam(Source: TDAParam)

Parameters:

  • Source: Instance whose properties will be copied

Clear    (declared in TDABaseField)

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

procedure Clear

GetDisplayName  protected override    (declared in TDABaseField)

Returns Name of the field

function GetDisplayName: string

GetIsNull  protected virtual    (declared in TDABaseField)

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

function GetIsNull: boolean

GetNamePath  override    (declared in TDABaseField)

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

function GetNamePath: string

HasValidDictionaryField  virtual    (declared in TDABaseField)

Indicates if the field has appropriate data dictionary entry

function HasValidDictionaryField: Boolean

IsCompatibleV4  protected virtual    (declared in TDABaseField)

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

function IsCompatibleV4: boolean

LoadFromFile

Reads Value from file.

procedure LoadFromFile(const aFileName: string)

Parameters:

  • aFileName: given file name.

LoadFromStream

Reads Value from stream.

procedure LoadFromStream(const aStream: IROStream)

Parameters:

  • aStream: given stream.

MergeDatadictionaries  protected virtual    (declared in TDABaseField)

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

SaveToFile

Writes Value to file.

procedure SaveToFile(const aFileName: string)

Parameters:

  • aFileName: given file name.

SaveToStream

Writes Value to stream.

procedure SaveToStream(const aStream: IROStream)

Parameters:

  • aStream: given stream.

SetDisplayName  protected override    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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    (declared in TDABaseField)

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