firemonkey android crc16 结果与 windows 的 delphi 不匹配
firemonkey android crc16 result mismatch with delphi for windows
在两个不同的项目中,我需要在 windows 中使用 crc16 checksum.one,而在 android.i 中的其他项目使用了 windows 的代码,并且效果很好。
showmessage( bin2crc16(HexToBin('1234')) ); //---> 0EC9
这里是winsows用到的函数
function Pow(i, k: Integer): Integer;
var
j, Count: Integer;
begin
if k>0 then j:=2
else j:=1;
for Count:=1 to k-1 do
j:=j*2;
Result:=j;
end;
function BinToDec(Str: string): Integer;
var
Len, Res, i: Integer;
Error: Boolean;
begin
Error:=False;
Len:=Length(Str);
Res:=0;
for i:=1 to Len do
if (Str[i]='0')or(Str[i]='1') then
Res:=Res+Pow(2, Len-i)*StrToInt(Str[i])
else
begin
//MessageDlg('It is not a binary number', mtInformation, [mbOK], 0);
Error:=True;
Break;
end;
if Error=True then Result:=0
else Result:=Res;
end;
//------------------------------------------------------------------------------
function CRC16CCITT(bytes: array of Byte): Word;
const
polynomial = 21;
var
crc: Word;
I, J: Integer;
b: Byte;
bit, c15: Boolean;
begin
crc := $FFFF;
for I := 0 to High(bytes) do
begin
b := bytes[I];
for J := 0 to 7 do
begin
bit := (((b shr (7-J)) and 1) = 1);
c15 := (((crc shr 15) and 1) = 1);
crc := crc shl 1;
if ((c15 xor bit) <> false) then crc := crc xor polynomial;
end;
end;
Result := crc and $ffff;
end;
//------------------------------------------------------------------------------
function HexToDec(const Str: string): Integer;
begin
if (Str <> '') and ((Str[1] = '-') or (Str[1] = '+')) then
Result := StrToInt(Str[1] + '$' + Copy(Str, 2, MaxInt))
else
Result := StrToInt('$' + Str);
end;
//------------------------------------------------------------------------------
function bin2crc16(str: string): string;
var
I:integer;
lengthCount : integer;
crcByteArr : array of Byte;
crcOut : Word;
begin
lengthCount := Trunc(length(str)/8);
setlength(crcByteArr , lengthCount );
for I := 0 to lengthCount-1 do
begin
crcByteArr[I] := BinToDec(copy(str, I*8+1, 8));
end;
crcOut := CRC16CCITT(crcByteArr);
result := crcOut.ToHexString;
end;
//------------------------------------------------------------------------------
function HexToBin(Hexadecimal: string): string;
const
BCD: array [0..15] of string =
('0000', '0001', '0010', '0011', '0100', '0101', '0110', '0111',
'1000', '1001', '1010', '1011', '1100', '1101', '1110', '1111');
var
i: integer;
begin
Result := '';
for i := Length(Hexadecimal) downto 1 do
Result := BCD[StrToInt('$' + Hexadecimal[i])] + Result;
end;
但对于 android,我更改了代码以处理零索引字符串。
结果不同
memo2.Lines.Add( bin2crc16(HexToBin('1234')) ); //-----> 1AFa
这里是android
中用到的函数
function BinToDec(Str: string): Integer;
var
Len, Res, i: Integer;
Error: Boolean;
begin
Error:=False;
Len:=Length(Str);
Res:=0;
for i:=0 to Len-1 do
if (Str[i]='0')or(Str[i]='1') then
Res:=Res+Pow(2, Len-i)*StrToInt(Str[i])
else
begin
Error:=True;
Break;
end;
if Error=True then Result:=0
else Result:=Res;
end;
//------------------------------------------------------------------------------
function CRC16CCITT(bytes: array of Byte): Word;
const
polynomial = 21;
var
crc: Word;
I, J: Integer;
b: Byte;
bit, c15: Boolean;
begin
crc := $FFFF;
for I := 0 to High(bytes) do
begin
b := bytes[I];
for J := 0 to 7 do
begin
bit := (((b shr (7-J)) and 1) = 1);
c15 := (((crc shr 15) and 1) = 1);
crc := crc shl 1;
if ((c15 xor bit) <> false) then crc := crc xor polynomial;
end;
end;
Result := crc and $ffff;
end;
//------------------------------------------------------------------------------
function bin2crc16(str: string): string;
var
I:integer;
lengthCount : integer;
crcByteArr : array of Byte;
crcOut : Word;
begin
lengthCount := Trunc(length(str)/8);
setlength(crcByteArr , lengthCount );
for I := 0 to lengthCount-1 do
begin
crcByteArr[I] := BinToDec(copy(str, I*8, 8));
end;
crcOut := CRC16CCITT(crcByteArr);
result := crcOut.ToHexString;
end;
//-----------------------------------------------------------------------------------
function HexToBin(Hexadecimal: string): string;
const
BCD: array [0..15] of string =
('0000', '0001', '0010', '0011', '0100', '0101', '0110', '0111',
'1000', '1001', '1010', '1011', '1100', '1101', '1110', '1111');
var
i: integer;
begin
Result := '';
for i := Length(Hexadecimal)-1 downto 0 do
Result := BCD[StrToInt('$' + Hexadecimal[i])] + Result;
end;
//---------------------------------------------------------------------------------
function Pow(i, k: Integer): Integer;
var
j, Count: Integer;
begin
if k>0 then j:=2
else j:=1;
for Count:=1 to k-1 do
j:=j*2;
Result:=j;
end;
我该如何解决我的问题!?
您还没有针对零长度字符串调整 HexToBin 函数。
您的 BinToDec 函数也有问题。您的功率计算是错误的,因为字符串中的索引已更改。可能最简单的处理方法如下,尽管您也可以在 POW 函数中调整索引
function BinToDec(Str: string): Integer;
var
Len, Res, i: Integer;
Error: Boolean;
begin
Error:=False;
Len:=Length(Str);
Res:=0;
for i:=1 to Len do
if (Str[I - 1]='0')or(Str[I - 1]='1') then
Res:=Res+Pow(2, Len-i)*StrToInt(Str[I - 1])
else
begin
Error:=True;
Break;
end;
if Error=True then Result:=0
else Result:=Res;
end;
最后要注意的是 'Copy' 即使在基于零的字符串上也使用基于一的索引,但您假设它是零索引的。我同意这令人困惑,但确实如此。
在两个不同的项目中,我需要在 windows 中使用 crc16 checksum.one,而在 android.i 中的其他项目使用了 windows 的代码,并且效果很好。
showmessage( bin2crc16(HexToBin('1234')) ); //---> 0EC9
这里是winsows用到的函数
function Pow(i, k: Integer): Integer;
var
j, Count: Integer;
begin
if k>0 then j:=2
else j:=1;
for Count:=1 to k-1 do
j:=j*2;
Result:=j;
end;
function BinToDec(Str: string): Integer;
var
Len, Res, i: Integer;
Error: Boolean;
begin
Error:=False;
Len:=Length(Str);
Res:=0;
for i:=1 to Len do
if (Str[i]='0')or(Str[i]='1') then
Res:=Res+Pow(2, Len-i)*StrToInt(Str[i])
else
begin
//MessageDlg('It is not a binary number', mtInformation, [mbOK], 0);
Error:=True;
Break;
end;
if Error=True then Result:=0
else Result:=Res;
end;
//------------------------------------------------------------------------------
function CRC16CCITT(bytes: array of Byte): Word;
const
polynomial = 21;
var
crc: Word;
I, J: Integer;
b: Byte;
bit, c15: Boolean;
begin
crc := $FFFF;
for I := 0 to High(bytes) do
begin
b := bytes[I];
for J := 0 to 7 do
begin
bit := (((b shr (7-J)) and 1) = 1);
c15 := (((crc shr 15) and 1) = 1);
crc := crc shl 1;
if ((c15 xor bit) <> false) then crc := crc xor polynomial;
end;
end;
Result := crc and $ffff;
end;
//------------------------------------------------------------------------------
function HexToDec(const Str: string): Integer;
begin
if (Str <> '') and ((Str[1] = '-') or (Str[1] = '+')) then
Result := StrToInt(Str[1] + '$' + Copy(Str, 2, MaxInt))
else
Result := StrToInt('$' + Str);
end;
//------------------------------------------------------------------------------
function bin2crc16(str: string): string;
var
I:integer;
lengthCount : integer;
crcByteArr : array of Byte;
crcOut : Word;
begin
lengthCount := Trunc(length(str)/8);
setlength(crcByteArr , lengthCount );
for I := 0 to lengthCount-1 do
begin
crcByteArr[I] := BinToDec(copy(str, I*8+1, 8));
end;
crcOut := CRC16CCITT(crcByteArr);
result := crcOut.ToHexString;
end;
//------------------------------------------------------------------------------
function HexToBin(Hexadecimal: string): string;
const
BCD: array [0..15] of string =
('0000', '0001', '0010', '0011', '0100', '0101', '0110', '0111',
'1000', '1001', '1010', '1011', '1100', '1101', '1110', '1111');
var
i: integer;
begin
Result := '';
for i := Length(Hexadecimal) downto 1 do
Result := BCD[StrToInt('$' + Hexadecimal[i])] + Result;
end;
但对于 android,我更改了代码以处理零索引字符串。 结果不同
memo2.Lines.Add( bin2crc16(HexToBin('1234')) ); //-----> 1AFa
这里是android
中用到的函数function BinToDec(Str: string): Integer;
var
Len, Res, i: Integer;
Error: Boolean;
begin
Error:=False;
Len:=Length(Str);
Res:=0;
for i:=0 to Len-1 do
if (Str[i]='0')or(Str[i]='1') then
Res:=Res+Pow(2, Len-i)*StrToInt(Str[i])
else
begin
Error:=True;
Break;
end;
if Error=True then Result:=0
else Result:=Res;
end;
//------------------------------------------------------------------------------
function CRC16CCITT(bytes: array of Byte): Word;
const
polynomial = 21;
var
crc: Word;
I, J: Integer;
b: Byte;
bit, c15: Boolean;
begin
crc := $FFFF;
for I := 0 to High(bytes) do
begin
b := bytes[I];
for J := 0 to 7 do
begin
bit := (((b shr (7-J)) and 1) = 1);
c15 := (((crc shr 15) and 1) = 1);
crc := crc shl 1;
if ((c15 xor bit) <> false) then crc := crc xor polynomial;
end;
end;
Result := crc and $ffff;
end;
//------------------------------------------------------------------------------
function bin2crc16(str: string): string;
var
I:integer;
lengthCount : integer;
crcByteArr : array of Byte;
crcOut : Word;
begin
lengthCount := Trunc(length(str)/8);
setlength(crcByteArr , lengthCount );
for I := 0 to lengthCount-1 do
begin
crcByteArr[I] := BinToDec(copy(str, I*8, 8));
end;
crcOut := CRC16CCITT(crcByteArr);
result := crcOut.ToHexString;
end;
//-----------------------------------------------------------------------------------
function HexToBin(Hexadecimal: string): string;
const
BCD: array [0..15] of string =
('0000', '0001', '0010', '0011', '0100', '0101', '0110', '0111',
'1000', '1001', '1010', '1011', '1100', '1101', '1110', '1111');
var
i: integer;
begin
Result := '';
for i := Length(Hexadecimal)-1 downto 0 do
Result := BCD[StrToInt('$' + Hexadecimal[i])] + Result;
end;
//---------------------------------------------------------------------------------
function Pow(i, k: Integer): Integer;
var
j, Count: Integer;
begin
if k>0 then j:=2
else j:=1;
for Count:=1 to k-1 do
j:=j*2;
Result:=j;
end;
我该如何解决我的问题!?
您还没有针对零长度字符串调整 HexToBin 函数。
您的 BinToDec 函数也有问题。您的功率计算是错误的,因为字符串中的索引已更改。可能最简单的处理方法如下,尽管您也可以在 POW 函数中调整索引
function BinToDec(Str: string): Integer;
var
Len, Res, i: Integer;
Error: Boolean;
begin
Error:=False;
Len:=Length(Str);
Res:=0;
for i:=1 to Len do
if (Str[I - 1]='0')or(Str[I - 1]='1') then
Res:=Res+Pow(2, Len-i)*StrToInt(Str[I - 1])
else
begin
Error:=True;
Break;
end;
if Error=True then Result:=0
else Result:=Res;
end;
最后要注意的是 'Copy' 即使在基于零的字符串上也使用基于一的索引,但您假设它是零索引的。我同意这令人困惑,但确实如此。