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Hextoint
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Question/Problem/Abstract:
Delphi kindly gave us IntToHex, but forgot to supply it's counterpart HexToInt.
(IntToHex converts a number into a string containing the number's hexadecimal
(base 16) representation)
Also no binary functions are in the sysutils unit, IntToBin and BinToInt.
Here's how to implement the missing functionality.
Uses Delphi 5 Int64 type but can be modified for all Delphi versions.
***************************************
{ ======================================= }
{ Convert a HexString value to an Int64 }
{ Note : Last Char can be 'H' for Hex }
{ eg. '00123h' or '00123H' }
{ 0 will be returned if invalid HexString }
{ ======================================= }
function HexToInt(HexStr : string) : Int64;
var RetVar : Int64;
i : byte;
begin
HexStr := UpperCase(HexStr);
if HexStr[length(HexStr)] = 'H' then
Delete(HexStr,length(HexStr),1);
RetVar := 0;
for i := 1 to length(HexStr) do begin
RetVar := RetVar shl 4;
if HexStr[i] in ['0'..'9'] then
RetVar := RetVar + (byte(HexStr[i]) - 48)
else
if HexStr[i] in ['A'..'F'] then
RetVar := RetVar + (byte(HexStr[i]) - 55)
else begin
Retvar := 0;
break;
end;
end;
Result := RetVar;
end;
{ ============================================== }
{ Convert an Int64 value to a binary string }
{ NumBits can be 64,32,16,8 to indicate the }
{ return value is to be Int64,DWord,Word }
{ or Byte respectively (default = 64) }
{ NumBits normally are only required for }
{ negative input values }
{ ============================================== }
function IntToBin(IValue : Int64; NumBits : word = 64) : string;
var RetVar : string;
i,ILen : byte;
begin
RetVar := '';
case NumBits of
32 : IValue := dword(IValue);
16 : IValue := word(IValue);
8 : IValue := byte(IValue);
end;
while IValue <> 0 do begin
Retvar := char(48 + (IValue and 1)) + RetVar;
IValue := IValue shr 1;
end;
if RetVar = '' then Retvar := '0';
Result := RetVar;
end;
{ ============================================== }
{ Convert a bit binary string to an Int64 value }
{ Note : Last Char can be 'B' for Binary }
{ eg. '001011b' or '001011B' }
{ 0 will be returned if invalid BinaryString }
{ ============================================== }
function BinToInt(BinStr : string) : Int64;
var i : byte;
RetVar : Int64;
begin
BinStr := UpperCase(BinStr);
if BinStr[length(BinStr)] = 'B' then Delete(BinStr,length(BinStr),1);
RetVar := 0;
for i := 1 to length(BinStr) do begin
if not (BinStr[i] in ['0','1']) then begin
RetVar := 0;
Break;
end;
RetVar := (RetVar shl 1) + (byte(BinStr[i]) and 1) ;
end;
Result := RetVar;
end;
***************************************
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Int2Bin
Jan Horn (Sep 28 2000 1:58AM)
Converts a 32bit integer to a binary number.
function Base10(Base2:Integer) : Integer; assembler;
asm
cmp eax,100000000 // check upper limit
jb @1 // ok
mov eax,-1 // error flag
jmp @exit // exit with -1
@1:
push ebx // save registers
push esi
xor esi,esi // result = 0
mov ebx,10 // diveder base 10
mov ecx,8 // 8 nibbles (10^8-1)
@2:
mov edx,0 // clear remainder
div ebx // eax DIV 10, edx mod 10
add esi,edx // result = result + remainder[I]
ror esi,4 // shift nibble
loop @2 // loop for all 8 nibbles
mov eax,esi // function result
pop esi // restore registers
pop ebx
@exit:
end;
***************************************
Here is another small HexToInt function
function HexToInt(HexString : String) : Integer;
var
s : string;
begin
s := '$' + HexString;
result := StrToInt(a);
end;
***************************************
{---------------------------------------------------------------------}
Function Hex2Int(S : String) : LongInt;
Const
HexChars : String[16] = '0123456789ABCDEF';
Var
I : Integer;
Begin
Result := 0;
For I := 1 to Length(S) do
Begin
Result := Result shl 4;
Result := Result or (Pos(S[I],HexChars) - 1);
End;
End;
{---------------------------------------------------------------------}
Function HexStr(LI : LongInt; Cnt : Byte) : String;
Const
HexCharArr : Array[0..$F] of Char =
('0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F');
Var
I : Integer;
Begin
For I := 0 to Cnt-1 do
Result := HexCharArr[ ((LI shr (4 * I)) and $000F) ] + Result;
End;
{---------------------------------------------------------------------}
***************************************
function BinToInt (BinStr: string) : Int64;
var
I, Len: integer;
const
Mask: int64 = 1;
begin
Result := 0;
Len := Length (BinStr);
if (UpperCase (BinStr [Len]) = 'B') then begin
Dec (Len);
end; {if}
for I := 1 to Len do begin
case BinStr [I] of
'0':
begin
{do nothing}
end;
'1':
begin
Result := Result OR (Mask SHL (Len - I))
end;
else begin
raise Exception.Create ('Wrong binary string');
end;
end; {case}
end; {for I}
end;
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