TDateTimeField Class

TDateTimeField represents a date-time field in a dataset.

Pascal

TDateTimeField = class(TField);

C++

class TDateTimeField : public TField;

File

Description

TDateTimeField encapsulates the fundamental behavior common to Date-time fields. Date-time fields contain combined date and time information, sometimes called timestamps. TDateTimeField introduces new properties to convert between date-time values and other data types, and to format the value of a date-time field for display.

Note: Date-time values accessed through dbExpress use TSQLTimeStampField instead of TDateTimeField

If you use the Fields editor at design time to create a persistent field component for the date-time field, you can access it by name at runtime. When using dynamic field components, you can access the TDateTimeField instance using the dataset's Fields property or FieldByName method.

Delphi Examples:

Copy Code

{
This example requires a button, a test edit, and a populated
ClientDataSet.  Pipe the ClientDataSet through a DataSource
to a DGGrid or DBNavigator to control the current field.
Cast the data correctly according to the field type when
assigning to the test edit.
}

{$IFNDEF UNICODE}
uses SwSystem;
{$ENDIF}

procedure TForm1.Button1Click(Sender: TObject);
var MyBuffer: Pointer;
begin
{ Retrieve the "raw" data from Field1 }
with CDS.Fields[0] do
  begin
    if not IsBlob then { this does not work for BLOB fields }
    begin
      { Allocate space }
      MyBuffer:= GetMemory(DataSize);
      try
        if not GetData(MyBuffer) then
          MessageDlg(DisplayName + ' is NULL', mtInformation, [mbOK], 0)
        else
          { Do something with the data };
          Edit1.Text:= string(PAnsiChar(MyBuffer)); // for a stringfield
      finally
        { Free the space }
        FreeMem(MyBuffer, DataSize);
      end;
    end;
  end;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
{$IFDEF UNICODE}
  CDS.LoadFromFile(GetCurrentDir + '\CDS.XML');
{$ELSE}
  CDS.LoadFromFile(gsAppPath + 'CDS.XML');
{$ENDIF}
end;