Delphi's question about the precision of decimal place

The round function uses the banker algorithm, which does not work.

Roundto is not so.

What format Ah,

Result: = Int (value * 100 + 0.5)/100;

All of them are not useful.

Figure out why, many times the result is: 17.145, but the fact is 17.1449999999, then you rounded two results is not right, especially money. Oh

In the online finally hunted to a master algorithm, we share the following:

class function Tnewdcfunc.roundfloat (F:double;i:integer):d ouble;
Var
s:string;
ef:extended;
Begin
S:= ' #. ' + Stringofchar (' 0 ', i);
Ef:=strtofloat (Floattostr (f));//Prevent errors in floating-point arithmetic
Result:=strtofloat (Formatfloat (S,EF));
End

Delphi's question about the precision of decimal place