Delphi的又一小缺陷: TDate赋值给Variant得到varDouble而不是varDate

Posted 2021-02-13 kinglandsoft

//Delphi 10.3.1 32bit, Win 7 32bit

procedure TForm1.btnTimeToVariantClick(Sender: TObject);
var
  d:TDate;
  t:TTime;
  v:Variant;
begin
  d := Date();
  t := Time();

  v := d;
  Assert( VarType(v)=varDouble );  //通过

  v := Variant(d);
  Assert( VarType(v)=varDouble );  //通过

  v := VarFromDateTime(d);
  Assert( VarType(v)=varDate );  //通过

  v := t;
  Assert( VarType(v)=varDouble );  //通过

  v := VarFromDateTime(t);;
  Assert( VarType(v)=varDate );  //通过

end;