Difference between revisions of "BitHelpers"

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==TWordBitHelper==
 
==TWordBitHelper==

Revision as of 20:23, 27 September 2018

About

BitHelpers enable additional bit manipulation for qword, longword, word, byte and boolean types which will make your life much easier if you need such a feature.

History

FreePascal type helpers TBooleanHelper, TByteHelper, TWordHelper, TCardinalHelper and TQWordHelper do not offer much when bit manipulation and presentation are needed. That's where BitHelpers package jumps in, nicely extending mentioned type helpers.

Installation

While you can simply copy bithelpers unit to your project directory and start using it, the recommended way would be to open "bithelpers_pkg.lpk" package and compile it. That would add BitHelpers source directory to Lazarus and make it available to all your projects.

Usage

TBooleanBitHelper

Example code and it's output:

  uses
    bithelpers;
  ...
  procedure TForm1.BooleanBitTestBtnClick(Sender: TObject);
  var
    MyBool: boolean;
  begin
    MyBool := true;
    Memo1.Append(MyBool.ToOneZeroString);
    Memo1.Append(MyBool.ToOnOffString); // default is scfUnchangedCase and can be ommited
    Memo1.Append(MyBool.ToOnOffString(scfLowerCase));
    Memo1.Append(MyBool.ToTrueFalseString(scfUpperCase));
    Memo1.Append(MyBool.ToString('OnState', 'OffState')); // true/false custom strings
    Memo1.Append(MyBool.ToString('Укључено', 'Искључено', scfUpperCase)); // when case and unicode matter
  end;
 1
 On
 on
 TRUE
 OnState
 УКЉУЧЕНО

TByteBitHelper

Example code and it's output:

  procedure TForm1.ByteBitTestBtnClick(Sender: TObject);
  var
    MyByte: byte;
  begin
    MyByte.Clear;                                  // %00000000 MyByte equals 0
    MyByte.Bit[0] := true;                         // %00000001 MyByte equals 1
    MyByte.Bit[2] := true;                         // %00000101 MyByte equals 5
    Memo1.Append(MyByte.ToString);
    Memo1.Append('$' + MyByte.ToHexString);
    Memo1.Append(MyByte.ToBooleanString(lzHideLeadingZeros));   // hide leading zeros
    Memo1.Append(MyByte.ToBooleanString);                       // show leading zeros   
  end;
 5
 $05
 101
 00000101

TWordBitHelper

Example code and it's output:

  procedure TForm1.WordBitTestBtnClick(Sender: TObject);
  var
    MyWord: word;
  begin
    MyWord.Clear;                  // %0000000000000000 MyWord equals 0
    MyWord.Byte[0] := 2;           // %0000000000000010 MyWord equals 2
    MyWord.Byte[1] := 1;           // %0000000100000010 MyWord equals 258 (2 + 256)
    MyWord.Byte[1].Bit[7] := true; // %0000000100000010 MyWord equals 258 (Beware!!! This DOES NOT set a bit in MyWord !!!)
    MyWord.Bit[10] := true;        // %0000010100000010 MyWord equals 1282 (258 + 2^10)
    Memo1.Append(MyWord.ToString);
    Memo1.Append('$' + MyWord.ToHexString);
    Memo1.Append(MyWord.ToBooleanString(lzHideLeadingZeros)); // hide leading zeros
    Memo1.Append(MyWord.ToBooleanString);                     // show leading zeros
  end;