数制转换

Question

十六进制数据转换成十进制数据,如将AB转换成十进制数.

Answer 1

function HexToDec(Hexa:string):integer;
const
  ValoresHexa:array['A'..'F'] of integer=(10,11,12,13,14,15);
var
  nDecimal:integer;
  nIndex:byte;
begin
  nDecimal:=0;
  Hexa:= Uppercase(Hexa);
  for nIndex:=length(Hexa) downTo 1 do
    if Hexa[nIndex] in ['0'..'9'] then
      nDecimal:=nDecimal+StrToInt(Hexa[nIndex])*
                Trunc(Exp(Length(Hexa)-nIndex)*ln(16)))
    else
      nDecimal:=nDecimal+ValoresHexa[Hexa[nIndex]]*
                Trunc(Exp(Length(Hexa)-nIndex)*ln(16)));
  result:=nDecimal;
end;

Answer 2

http://expert.csdn.net/Expert/topic/1330/1330990.xml?temp=.5624964