Unit 'DB' Package
[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] [#fcl]

TParam

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

Parameter description class.

Declaration

Source position: db.pas line 1385

type TParam = class(TCollectionItem)

public

  constructor Create();

  

Create a new parameter value.

  procedure Assign(); override;

  

Assign one parameter instance to another.

  procedure AssignField();

  

Copy value from field instance.

  procedure AssignToField();

  

Assign parameter value to field.

  procedure AssignFieldValue();

  

Assign field value to the parameter.

  procedure AssignFromField();

  

Copy field type and value.

  procedure Clear;

  

Clear the parameter value.

  procedure GetData();

  

Get the parameter value from a memory buffer.

  function GetDataSize;

  

Return the size of the data.

  procedure LoadFromFile();

  

Load a parameter value from file.

  procedure LoadFromStream();

  

Load a parameter value from stream.

  procedure SetBlobData();

  

Set BLOB data.

  procedure SetData();

  

Set the parameter value from a buffer.

  property AsBCD: Currency; [rw]

  

Get or set parameter value as BCD value.

  property AsBlob: TBlobData; [rw]

  

Return parameter value as a blob.

  property AsBoolean: Boolean; [rw]

  

Get/Set parameter value as a boolean value.

  property AsByte: LongInt; [rw]

  

Get/Set parameter value as a 8-bit unsigned integer value.

  property AsBytes: TBytes; [rw]

  

Get or set parameter value as TBytes.

  property AsCurrency: Currency; [rw]

  

Get/Set parameter value as a currency value.

  property AsDate: TDateTime; [rw]

  

Get/Set parameter value as a date (TDateTime) value.

  property AsDateTime: TDateTime; [rw]

  

Get/Set parameter value as a date/time (TDateTime) value.

  property AsFloat: Double; [rw]

  

Get/Set parameter value as a floating-point value.

  property AsInteger: LongInt; [rw]

  

Get/Set parameter value as an integer (32-bit) value.

  property AsLargeInt: LargeInt; [rw]

  

Get/Set parameter value as a 64-bit integer value.

  property AsLongWord: LongWord; [rw]

  

Get/Set parameter value as a 32-bit unsigned integer value.

  property AsMemo: string; [rw]

  

Get/Set parameter value as a memo (string) value.

  property AsShortInt: LongInt; [rw]

  property AsSingle: Single; [rw]

  property AsSmallInt: LongInt; [rw]

  

Get/Set parameter value as a smallint value.

  property AsString: string; [rw]

  

Get/Set parameter value as a string value.

  property AsAnsiString: AnsiString; [rw]

  

Parameter contents as an ANSI string.

  property AsUTF8String: UTF8String; [rw]

  

Parameter contents as an UTF8 string.

  property AsUnicodeString: UnicodeString; [rw]

  

Parameter contents as a Unicode string.

  property AsTime: TDateTime; [rw]

  

Get/Set parameter value as a time (TDateTime) value.

  property AsWord: LongInt; [rw]

  

Get/Set parameter value as a word value.

  property AsFMTBCD: TBCD; [rw]

  

Parameter value as a BCD value.

  property Bound: Boolean; [rw]

  

Is the parameter value bound (set to fixed value).

  property Dataset: TDataSet; [r]

  

Dataset to which this parameter belongs.

  property IsNull: Boolean; [r]

  

Is the parameter empty.

  property NativeStr: string; [rw]

  

No description available.

  property Text: string; [rw]

  

Read or write the value of the parameter as a string.

  property AsWideString: WideString; [rw]

  

Get/Set the value as a widestring.

published

  property DataType: TFieldType; [rw]

  

Data type of the parameter.

  property Name: string; [rw]

  

Name of the parameter.

  property NumericScale: Integer; [rw]

  

Numeric scale.

  property ParamType: TParamType; [rw]

  

Type of parameter.

  property Precision: Integer; [rw]

  

Precision of the BCD value.

  property Size: Integer; [rw]

  

Size of the parameter.

  property Value: Variant; [rws]

  

Value as a variant.

end;

Inheritance

TParam

  

Parameter description class.

|

TCollectionItem

|

TPersistent

|

TObject,IFPObserved

Description

TParam is one item in a TParams collection. It describes the name (TParam.Name), type (ParamType) and value (TParam.Value) of a parameter in a parameterized query or stored procedure. Under normal circumstances, it should never be necessary to create a TParam instance manually; the TDataset descendent that owns the parameters should have created all necessary TParam instances.

See also

TParams

  

A collection of parameter values for SQL-based datasets.


Documentation generated on: Nov 23 2024