delphi - Delphi:将多行字符串保存到文件

Question

大家晚上好。

我有一个StringList，每个记录包含一个多行字符串。

MyStringList [0]：

<li>
  Test1
</li>

MyStringList [1]：

<a href="#">
  <b>      
    Test2
  </b>
</a>

等等

如何将这些字符串保存并加载到文件（文本，ini，二进制，记录，savetofile等）中？主要问题是我可以将其保存到文本文件中，但是当回读时，每行被视为新记录，而第一条记录有3行，第二条记录有5行，依此类推。

您对保存和加载这些字符串的过程有何建议？

Answer 1

如果将其保存到.txt文件，则会失去正确重新加载它的功能，因为您不知道给定换行符最初是嵌入在字符串中还是分隔两个字符串。

如果将其保存为其他文本格式（如.ini），则可以根据需要对换行符进行转义/转义，例如：

function Encode(const S: String): String;
begin
  Result := StringReplace(S, '<', '<<', [rfReplaceAll]);
  Result := StringReplace(Result, #13#10, '<CRLF>', [rfReplaceAll]);
  Result := StringReplace(Result, #13, '<CR>', [rfReplaceAll]);
  Result := StringReplace(Result, #10, '<LF>', [rfReplaceAll]);
end;

Ini := TIniFile.Create(...);
try
  Ini.WriteInteger('section', 'count', MyStringList.Count);
  for I := 0 to MyStringList.Count-1 do
    Ini.WriteString('section', IntToStr(I), Encode(MyStringList[I]);
finally
  Ini.Free;
end;

function Decode(const S: String): String;
begin
  Result := StringReplace(S, '<LF>', #10, [rfReplaceAll]);
  Result := StringReplace(Result, '<CR>', #13, [rfReplaceAll]);
  Result := StringReplace(Result, '<CRLF>', #13#10, [rfReplaceAll]);
  Result := StringReplace(Result, '<<', '<', [rfReplaceAll]);

结束;

Ini := TIniFile.Create(...);
try
  Count := Ini.ReadInteger('section', 'count', 0);
  for I := 0 to Count-1 do
    MyStringList.Add(Decode(Ini.ReadString('section', IntToStr(I), ''));
finally
  Ini.Free;
end;

如果将其保存为二进制格式，则可以按原样保留换行符，例如：

procedure WriteIntegerToStream(Stream: TStream; Value: Integer);
begin
  Stream.WriteBuffer(Value, SizeOf(Integer));
end;

procedure WriteStringToStream(Stream: TStream; const Value: String);
var
  U: UTF8String;
  Count: Integer;
begin
  U := UTF8String(Value); // or UTF8Encode(Value) prior to D2009
  Count := Length(U);
  WriteIntegerToStream(Stream, Count);
  if Count > 0 then
    Stream.WriteBuffer(PAnsiChar(U)^, Count * SizeOf(AnsiChar));
end;

Strm := TFileStream.Create(..., fmCreate);
try
  WriteIntegerToStream(Stream, MyStringList.Count);
  for I := 0 to MyStringList.Count-1 do
    WriteStringToStream(Stream, MyStringList[I]);
finally
  Stream.Free;
end;

function ReadIntegerFromStream(Stream: TStream): Integer;
begin
  Stream.ReadBuffer(Result, SizeOf(Integer));
end;

function ReadStringFromStream(Stream: TStream): String;
var
  Count: Integer;
  U: UTF8String;
begin
  Count := ReadIntegerFromStream(Stream);
  if Count > 0 then
  begin
    SetLength(U, Count);
    Stream.ReadBuffer(PAnsiChar(U)^, Count * SizeOf(AnsiChar));
    Result := String(U); // or UTF8Decode(U) prior to D2009
  end else
    Result := '';
end;

Stream := TFileStream.Create(..., fmOpenRead or fmShareDenyWrite);
try
  Count := ReadIntegerFromStream(Stream);
  for I := 0 to Count-1 do
    MyStringList.Add(ReadStringFromStream(Stream));
finally
  Stream.Free;
end;