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This page displays 20 requested snippets.

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AddHexPrefix

Adds a hex prefix to a string of hex digits.

function AddHexPrefix(const HexStr: string): string;
begin
  Result := SysUtils.HexDisplayPrefix + StripHexPrefix(HexStr);
end;

Kind of Snippet: Routine

Required units: SysUtils.

Required snippets: StripHexPrefix.

See also: StripHexPrefix.

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

Prefix used is '$' when compiled on Delphi or '0x' when compiled on C++ Builder.

BufToHex

Returns a hexadecimal representation of the bytes in a buffer of a given size.

function BufToHex(const Buf; const Size: Cardinal): string;
const
  // maps nibbles to hex digits
  cHexDigits: array[$0..$F] of Char = (
    '0', '1', '2', '3', '4', '5', '6', '7',
    '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
  );
var
  I: Cardinal;  // loops thru output string
  PB: ^Byte;    // addresses each byte in buffer
begin
  PB := @Buf;
//  Result := '';
  SetLength(Result, 2 * Size);
  I := 1;
  while I <= 2 * Size do
  begin
    Result[I] := cHexDigits[PB^ shr 4];
    Result[I + 1] := cHexDigits[PB^ and $0F];
    Inc(PB);
    Inc(I, 2);
  end;
end;

Kind of Snippet: Routine

Required units: None.

Required snippets: None.

See also: BytesToHex, ByteToHex, LongWordToHex, QuadWordToHex, WordToHex, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

BytesToHex

Returns a hexadecimal representation of an array of bytes.

function BytesToHex(const Bytes: array of Byte): string;
begin
  Result := BufToHex(Bytes, Length(Bytes));
end;

Kind of Snippet: Routine

Required units: None.

Required snippets: BufToHex.

See also: BufToHex, ByteToHex, LongWordToHex, QuadWordToHex, WordToHex, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

ByteToHex

Returns the hexadecimal representation of a byte.

function ByteToHex(const B: Byte): string;
begin
  Result := SysUtils.IntToHex(B, 2 * SizeOf(B));
end;

Kind of Snippet: Routine

Required units: SysUtils.

Required snippets: None.

See also: BufToHex, BytesToHex, LongWordToHex, QuadWordToHex, WordToHex, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

HexByteSize

Returns the number of bytes represented by a hexadecimal string.

function HexByteSize(HexStr: string): Cardinal;
begin
  HexStr := StripHexPrefix(HexStr);
  Result := (Length(HexStr) div 2) + (Length(HexStr) mod 2);
end;

Kind of Snippet: Routine

Required units: None.

Required snippets: StripHexPrefix.

See also: HexToBuf.

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

HexToBuf

Writes the bytes represented by a hexadecimal string into a buffer, which must be large enough to receive the data.

procedure HexToBuf(HexStr: string; var Buf);
{$IFDEF FPC}
const
{$ELSE}
resourcestring
{$ENDIF}
  sHexConvertError = '''%s'' is not a valid hexadecimal string';
begin
  if not TryHexToBuf(HexStr, Buf) then
    raise SysUtils.EConvertError.CreateFmt(sHexConvertError, [HexStr]);
end;

Kind of Snippet: Routine

Required units: None.

Required snippets: TryHexToBuf.

See also: TryHexToBuf, HexToBytes, HexToInt, HexToInt64, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

HexToBytes

Writes the bytes represented by a hexadecimal string into an array. The array is sized accordingly.

function HexToBytes(HexStr: string): TBytes;
{$IFDEF FPC}
const
{$ELSE}
resourcestring
{$ENDIF}
  sHexConvertError = '''%s'' is not a valid hexadecimal string';
begin
  if not TryHexToBytes(HexStr, Result) then
    raise SysUtils.EConvertError.CreateFmt(sHexConvertError, [HexStr]);
end;

Kind of Snippet: Routine

Required units: None.

Required snippets: TBytes, TryHexToBytes, [Show All].

See also: TryHexToBytes, HexToBuf, HexToInt, HexToInt64, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

This snippet cannot be included in generated units.

HexToInt

Converts a hexadecimal string to an integer. Raises an exception if the string is not valid hexadecimal.

function HexToInt(const HexStr: string): Integer;
{$IFDEF FPC}
const
{$ELSE}
resourcestring
{$ENDIF}
  sHexConvertError = '''%s'' is not a valid hexadecimal value';
begin
  if not TryHexToInt(HexStr, Result) then
    raise SysUtils.EConvertError.CreateFmt(sHexConvertError, [HexStr]);
end;

Kind of Snippet: Routine

Required units: None.

Required snippets: TryHexToInt.

See also: TryHexToInt, HexToIntDef, HexToBuf, HexToBytes, HexToInt64, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

HexToInt64

Converts a hexadecimal string to a 64 bit integer. Raises an exception if the string is not valid hexadecimal.

function HexToInt64(const HexStr: string): Int64;
{$IFDEF FPC}
const
{$ELSE}
resourcestring
{$ENDIF}
  sHexConvertError = '''%s'' is not a valid hexadecimal value';
begin
  if not TryHexToInt64(HexStr, Result) then
    raise SysUtils.EConvertError.CreateFmt(sHexConvertError, [HexStr]);
end;

Kind of Snippet: Routine

Required units: None.

Required snippets: TryHexToInt64.

See also: TryHexToInt64, HexToInt64Def, HexToBuf, HexToBytes, HexToInt, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

HexToInt64Def

Converts a hexadecimal string to a 64 bit integer. If the conversion fails the specified default value is returned.

function HexToInt64Def(const HexStr: string; const Default: Int64): Int64;
begin
  if not TryHexToInt64(HexStr, Result) then
    Result := Default;
end;

Kind of Snippet: Routine

Required units: None.

Required snippets: TryHexToInt64.

See also: TryHexToInt64, HexToInt64, HexToIntDef, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

HexToIntDef

Converts a hexadecimal string to an integer. If the conversion fails the specified default value is returned.

function HexToIntDef(const HexStr: string; const Default: Integer): Integer;
begin
  if not TryHexToInt(HexStr, Result) then
    Result := Default;
end;

Kind of Snippet: Routine

Required units: None.

Required snippets: TryHexToInt.

See also: TryHexToInt, HexToInt, HexToInt64Def, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

LongWordToHex

Returns the hexadecimal representation of a long (4 byte) word.

function LongWordToHex(const LW: LongWord): string;
begin
  Result := SysUtils.IntToHex(Integer(LW), 2 * SizeOf(LW));
end;

Kind of Snippet: Routine

Required units: SysUtils.

Required snippets: None.

See also: BufToHex, BytesToHex, ByteToHex, QuadWordToHex, WordToHex, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

QuadWordToHex

Returns the hexadecimal representation of a quad (8 byte) word.

function QuadWordToHex(const QW: UInt64): string;
begin
  Result := SysUtils.IntToHex(Int64(QW), 2 * SizeOf(QW));
end;

Kind of Snippet: Routine

Required units: SysUtils.

Required snippets: None.

See also: BufToHex, BytesToHex, ByteToHex, LongWordToHex, WordToHex, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

StripHexPrefix

Strips any prefix from a hex string. Both Delphi ('$') and C ('0x') prefixes are supported.

function StripHexPrefix(const HexStr: string): string;
begin
  if Pos('$', HexStr) = 1 then
    Result := Copy(HexStr, 2, Length(HexStr) - 1)
  else if Pos('0x', SysUtils.LowerCase(HexStr)) = 1 then
    Result := Copy(HexStr, 3, Length(HexStr) - 2)
  else
    Result := HexStr;
end;

Kind of Snippet: Routine

Required units: SysUtils.

Required snippets: None.

See also: AddHexPrefix.

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

TryHexToBuf

Writes the bytes represented by a hexadecimal string into a buffer, which must be large enough to receive the data. Returns True on success or False if HexStr is either empty or contains invalid hex characters.

function TryHexToBuf(HexStr: string; var Buf): Boolean;
var
  I: Integer;       // loops through characters of string
  PB: ^Byte;        // references each byte in buffer
  ByteVal: Integer; // a byte value from hex string
begin
  Result := False;
  HexStr := StripHexPrefix(HexStr);
  if HexStr = '' then
    Exit;
  if Odd(Length(HexStr)) then
    HexStr := '0' + HexStr;
  I := 1;
  PB := @Buf;
  while I <= Length(HexStr) do
  begin
    if not TryHexToInt(HexStr[I] + HexStr[I + 1], ByteVal) then
      Exit;
    PB^ := Byte(ByteVal);
    Inc(I, 2);
    Inc(PB);
  end;
  Result := True;
end;

Kind of Snippet: Routine

Required units: None.

Required snippets: StripHexPrefix, TryHexToInt, [Show All].

See also: HexToBuf, TryHexToBytes, TryHexToInt, TryHexToInt64, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

TryHexToBytes

Writes the bytes represented by a hexadecimal string into a byte array. Returns True on success or False if HexStr is either empty or contains invalid hex characters.

function TryHexToBytes(HexStr: string; out Bytes: TBytes): Boolean;
begin
  SetLength(Bytes, HexByteSize(HexStr));
  Result := TryHexToBuf(HexStr, Bytes[0]);
end;

Kind of Snippet: Routine

Required units: None.

Required snippets: HexByteSize, TBytes, TryHexToBuf, [Show All].

See also: HexToBytes, TryHexToBuf, TryHexToInt, TryHexToInt64, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

This snippet cannot be included in generated units.

TryHexToInt

Converts a hexadecimal string to an integer. Returns True if the string was converted successfully and sets Value to the converted value. Returns False on error, leaving Value undefined.

function TryHexToInt(const HexStr: string; out Value: Integer): Boolean;
var
  E: Integer; // error code
begin
  Val(AddHexPrefix(HexStr), Value, E);
  Result := E = 0;
end;

Kind of Snippet: Routine

Required units: None.

Required snippets: AddHexPrefix.

See also: HexToInt, HexToIntDef, TryHexToBuf, TryHexToBytes, TryHexToInt64, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

TryHexToInt64

Converts a hexadecimal string to a 64 bit integer. Returns True if the string was converted successfully and sets Value to the converted value. Returns False on error, leaving Value undefined.

function TryHexToInt64(const HexStr: string; out Value: Int64): Boolean;
var
  E: Integer; // error code
begin
  Val(AddHexPrefix(HexStr), Value, E);
  Result := E = 0;
end;

Kind of Snippet: Routine

Required units: None.

Required snippets: AddHexPrefix.

See also: HexToInt64, HexToInt64Def, TryHexToBuf, TryHexToBytes, TryHexToInt, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

WordToHex

Returns the hexadecimal representation of a Word (2 bytes).

function WordToHex(const W: Word): string;
begin
  Result := SysUtils.IntToHex(W, 2 * SizeOf(W));
end;

Kind of Snippet: Routine

Required units: SysUtils.

Required snippets: None.

See also: BufToHex, BytesToHex, ByteToHex, LongWordToHex, QuadWordToHex, [Show All].

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

TBytes

Dynamic array of bytes. Ensures TBytes is available on non-Unicode compilers that don't define it in SysUtils.

type
  {$IFDEF UNICODE}
  TBytes = SysUtils.TBytes;
  {$ELSE}
  TBytes = array of Byte;
  {$ENDIF}

Kind of Snippet: Type Definition

Required units: SysUtils.

Required snippets: None.

See also: None.

Supported Compilers:

D2	D3	D4	D5	D6	D7	D2005 (Win32)	D2006 (Win32)	D2007	D2009 (Win32)	D2010 (Win32)	Free Pascal

This snippet cannot be included in generated units.