Significant Digits - Extended Data Type?

[UKChris]

My number seems to be truncating, is Extended the data type with the greatest range? Int he following code:

procedure TForm1.Button2Click(Sender: TObject);
var a : extended;
begin
a := 1.123456789123456789;
showmessage(floattostr(a));
end;

The Message shows as 1.12345678912346 seems it only deals with 16 digits. Can I increase this? I really need 20, or more digits.

Chris.

 

[UKChris]

With help from elsewhere it seems this does it for me:

showmessage(floattostrF(a,ffGeneral,18,18));

Lucky that 18 digits will do it for my app!

Chris.

 

[TealWren]

I think you can also use formatfloat, with the format specifier #.###################

FormatFloat('#.###################',a)

Or you can use zeros instead of #'s to force it to show the decimal places even if they are zero.

TealWren