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There is a newer version: 1.12.1

Why is this an issue?

  Casting a Unicode type like String to an ANSI type like AnsiString can
  lead to data loss. Because any given ANSI code page contains only a small subset of Unicode
  characters, converting a Unicode type to ANSI will cause all non-ANSI characters to be replaced
  with question marks.

How to fix it

  Code that casts Unicode types directly to ANSI types are generally problematic on a design level.
  As such, there is no single solution.


  If you are casting to AnsiString to get the string as bytes, consider using
  TEncoding.GetBytes to convert the contents of the string into bytes using a specific
  encoding:

procedure WriteToFile(MyStr: string);
var
  MyAnsiStr: AnsiString;
  MyStream: TFileStream;
begin
  MyAnsiStr := AnsiString(MyStr);

  MyStream := TFileStream.Create('myfile.txt');
  try
    MyStream.WriteBuffer(MyAnsiStr[1], Length(MyAnsiStr));
  finally
    FreeAndNil(MyStream);
  end;
end;

procedure WriteToFile(MyStr: string);
var
  MyBytes: TBytes;
  MyStream: TFileStream;
begin
  MyBytes := TEncoding.ANSI.GetBytes(MyStr);

  MyStream := TFileStream.Create('myfile.txt');
  try
    MyStream.WriteBuffer(MyBytes, Length(MyBytes));
  finally
    FreeAndNil(MyStream);
  end;
end;


  If you are casting to AnsiString to pass to a WinAPI routine, use a
  WideString overload instead.

Resources

  
    
      RAD Studio documentation: Unicode in RAD Studio
    
  
  
    
      RAD Studio API documentation: System.SysUtils.TEncoding.GetBytes