Delphi下常用转换
作者:lyboy99
e-mail:lyboy99@sina.com
url: http://hnh.126.com
给大家提供几个常用的转换方法和其转换函数
希望可以对你有帮助
1.HEX -> Integer
2.2.Dec To HEX
3.ASCII to HEX / math
4.Binary to decimal
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1.HEX -> Integer
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方法. 1
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var
i : integer
s : string;
begin
s := '$' + ThatHexString;
i := StrToInt(a);
end;
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方法. 2
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CONST HEX : ARRAY['A'..'F'] OF INTEGER = (10,11,12,13,14,15);
VAR str : String;
Int,
i : integer;
BEGIN
READLN(str);
Int := 0;
FOR i := 1 TO Length(str) DO
IF str[i] < 'A' THEN Int := Int * 16 + ORD(str[i]) - 48
ELSE Int := Int * 16 + HEX[str[i]];
WRITELN(Int);
READLN;
END.
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2.Dec To HEX
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HexString := Format('%0x',DecValue);
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3.ASCII to HEX / math
------------------------
unit Hexstr;
interface
uses String16, SysUtils;
Type
PByte = ^BYTE;
procedure BytesToHexStr(var hHexStr: String; pbyteArray: PByte; InputLength: WORD);
procedure HexStrToBytes(hHexStr: String; pbyteArray: Pointer);
procedure HexBytesToChar(var Response: String; hexbytes: PChar; InputLength: WORD);
implementation
procedure BytesToHexStr(var hHexStr: String; pbyteArray: PByte; InputLength: WORD);
Const
HexChars : Array[0..15] of Char = '0123456789ABCDEF';
var
i, j: WORD;
begin
SetLength(hHexStr, (InputLength * 2));
FillChar(hHexStr, sizeof(hHexStr), #0);
j := 1;
for i := 1 to InputLength do begin
hHexStr[j] := Char(HexChars[pbyteArray^ shr 4]); inc(j);
hHexStr[j] := Char(HexChars[pbyteArray^ and 15]); inc(j);
inc(pbyteArray);
end;
end;
procedure HexBytesToChar(var Response: String; hexbytes: PChar; InputLength: WORD);
var
i: WORD;
c: byte;
begin
SetLength(Response, InputLength);
FillChar(Response, SizeOf(Response), #0);
for i := 0 to (InputLength - 1) do begin
c := BYTE(hexbytes[i]) And BYTE($f);
if c > 9 then
Inc(c, $37)
else
Inc(c, $30);
Response[i + 1] := char(c);
end;{for}
end;
procedure HexStrToBytes(hHexStr: String; pbyteArray: Pointer);
{pbyteArray must point to enough memory to hold the output}
var
i, j: WORD;
tempPtr: PChar;
twoDigits : String[2];
begin
tempPtr := pbyteArray;
j := 1;
for i := 1 to (Length(hHexStr) DIV 2) do begin
twoDigits := Copy(hHexStr, j, 2); Inc(j, 2);
PByte(tempPtr)^ := StrToInt('$' + twoDigits); Inc(tempPtr);
end;{for}
end;
end.
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UNIT String16.
interface
{$IFNDEF Win32}
procedure SetLength(var S: string; Len: Integer);
procedure SetString(var Dst: string; Src: PChar; Len: Integer);
{$ENDIF}
implementation
{$IFNDEF Win32}
procedure SetLength(var S: string; Len: Integer);
begin
if Len > 255 then
S[0] := Chr(255)
else
S[0] := Chr(Len)
end;
procedure SetString(var Dst: string; Src: PChar; Len: Integer);
begin
if Len > 255 then
Move(Src^, Dst[1], 255)
else
Move(Src^, Dst[1], Len);
SetLength(Dst, Len);
end;
{$ENDIF}
end.
=================================================================
4.Binary to decimal
-----------------------------------------------------------------
////////////////////////////////////////////////
// convert 32 bit base2 to 32 bit base10 //
// max number = 99 999 999, return -1 if more //
////////////////////////////////////////////////
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;
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方法. 2
[Oliver Townshend, oliver@zip.com.au]
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function IntToBin(Value: LongInt;Size: Integer): String;
var
i: Integer;
begin
Result:='';
for i:=Size downto 0 do begin
if Value and (1 shl i)<>0 then begin
Result:=Result+'1';
end else begin
Result:=Result+'0';
end;
end;
end;
function BinToInt(Value: String): LongInt;
var
i,Size: Integer;
begin
Result:=0;
Size:=Length(Value);
for i:=Size downto 0 do begin
if Copy(Value,i,1)='1' then begin
Result:=Result+(1 shl i);
end;
end;
end;
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