BaseNcodingPascal下载 - BaseNcodingPascal源代码下载

BaseNcodingPascal

Delphi源码

1.0.0

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Basencodingpascal

这是帕斯卡尔的底座编码的港口。

有二进制数据的算法众所周知，用于字符串编码，例如具有2（base32，base64）的电源的算法和无功率为2（base85，base91）的算法。

该库实现了一般情况的算法，即可以使用自定义字母（具有自定义长度的字母）。

开发算法的概念基于Base85编码，除了块大小不是恒定的，而是根据字母长度计算的。

###算法的步骤

计算位和字符中的块大小。
将输入字符串转换为字节数组（使用UTF8编码）。
在n位组上分裂字节阵列。
每个小组与radix n的对话。
尾部处理。

对于最佳块大小计算，已使用以下考虑：

在此系统中：

A - 字母长度a 。
K - 编码字符的计数。
b - 一个数字radix基座（大多数情况下为2个）。
n - radix b中的位用于表示字母a的k字符a。
R - 压缩比（更大的比较更好）。
MBC-最大块位计数。
⌊x⌋-最大的整数不大于x（地板）。
⌈x⌉-最小的整数不小于x（天花板）。

最佳块大小和字母长度依赖性的图是在上述系统的帮助下计算的：

可以看到已知的基本64，base85，base91编码已经以优点开发（最小的块大小具有良好的压缩比）。

对于BITS块到Chars块，我的Biginteger库中的BigInteger实现使用了一些微小的修改。

Porting guidelines:

 1. All file names (units) are the same, but with a "u" prefix. 
2. Some variables were closely named. 
3. Some functions were written by me because I could not find a Delphi/
   FreePascal Equivalent of the C# function used, in the RTL or for Backwards
   Compatibility with older Unicode versions of Delphi or FreePascal.

Hints about the code:

 1.  Multi-condition "for" loops and loops where iterator gets changed inside 
  the loop were converted to while loops. 

2.  Log method (Delphi/FreePascal Equivalent "LogN"), two arguments (a, newBase) needed to be 
    swapped in Delphi/FreePascal.   

3.  This Library was written with (Delphi 10 Seattle Update 1) but will 
    work fine with anything from Delphi 2010 and FreePascal 3.0.0 Upwards.

4.  "Parallel version" was implemented using PPL (Parallel Programming Library) 
     but will only work in Delphi XE7 Upwards.

5.  This Library was written with the Object Oriented Paradigm (Class-Based) but 
    implements memory management through reference counting with the help of 
    Interfaces (that is, created objects or class instances are "freed" once they 
    go out of scope).

6. If you are working with FreePascal in which the String and Char types are Mapped 
   to "AnsiString" and "AnsiChar" by Default, you could "remap" them to "UnicodeString" 
   and "UnicodeChar" by declaring "{$mode delphiunicode}" at the top of your unit 
   excluding the ("") symbols.

Common pitfalls during porting:

 1. Calling Log methods without swapping arguments places.
2. Writing for .. to .. do loop instead of for .. downto .. do in rare cases.
3. Differences in Order of Operator Precedence between C# and Pascal.

###代码示例

     // Here is a Little Snippet showing Usage for Base32 Operations.  
    uses
      SysUtils, BcpBase32, BcpIBaseInterfaces, BcpBaseFactory;

      procedure TForm1.Button1Click (Sender: TObject);
	var
	  B32: IBase32;
	  EncodedString, DecodedString, BaseAlphabet: { $IFDEF FPC } UnicodeString { $ELSE } String { $ENDIF } ;
	  DecodedArray: TBytes;
	  BaseSpecial: { $IFDEF FPC } UnicodeChar { $ELSE } Char { $ENDIF } ;
	begin
	  // Creates a Base32 Instance with Default Values. You can Specify your Desired 
	  // Parameters During Creation of the Instance.
	  B32 := TBase32.Create();
	  // Accepts a String and Encodes it Internally using UTF8 as the Default Encoding
	  EncodedString := B32.EncodeString( ' TestValue ' );
	  // Accepts an Encoded String and Decodes it Internally using UTF8 as the Default Encoding
	  DecodedString := B32.DecodeToString(EncodedString);
	  // Accepts a Byte Array and Encodes it.
	  EncodedString := B32.Encode(TEncoding.ANSI.GetBytes( ' TestValue ' ));
	  // Accepts an Encoded String and Decodes it. (Returns a Byte Array)
	  DecodedArray := B32.Decode(EncodedString);
	  // Property that allows you to modifies The Encoding of the Created Instance.
	  B32.Encoding := TEncoding.Unicode;
	  // Property that allows you to get The Base Alphabets used to perform the Encoding.
	  BaseAlphabet := B32.Alphabet;
	  // Property that allows you to get The Base Char (Padder) used to perform the Encoding.
	  BaseSpecial := B32.Special;
	 // There are some other important properties but those are left for you to figure out. :)
	 // Also no need to "Free" the Created Instance Since it is Reference Counted.
	// or for a simple one-liner to Base32 Encode a String
	  TBaseFactory.CreateBase32().EncodeString( ' Fish ' );
    end ;

单位测试。

要运行单元测试，

对于FPC 3.0.0及以上

 Simply compile and run "BaseNcoding.Tests" project in "FreePascal.Tests" Folder.

对于Delphi 2010及以上

方法一（使用Dunit测试跑者）

 To Build and Run the Unit Tests For Delphi 10 Seattle (should be similar for 
 other versions)

1). Open Project Options of Unit Test (BaseNcoding.Tests) in "Delphi.Tests" Folder.

2). Change Target to All Configurations (Or "Base" In Older Delphi Versions.)

3). In Output directory add ".$(Platform)$(Config)" without the quotes.

4). In Search path add "$(BDS)SourceDUnitsrc" without the quotes.

5). In Unit output directory add "." without the quotes.

6). In Unit scope names (If Available), Delete "DUnitX" from the List.

Press Ok and save, then build and run.

方法两个（使用TestInsight）（首选）。

 1). Download and Install TestInsight.

2). Open Project Options of Unit Test (BaseNcoding.Tests.TestInsight) in "Delphi.Tests" 
    Folder. 

3). Change Target to All Configurations (Or "Base" In Older Delphi Versions.)

4). In Unit scope names (If Available), Delete "DUnitX" from the List.

5). To Use TestInsight, right-click on the project, then select 
	"Enable for TestInsight" or "TestInsight Project".
    Save Project then Build and Run Test Project through TestInsight.

＃＃＃执照

此“软件”是根据MIT License (MIT)许可的。