delphi 5个方法读取文本内容到memo

代码0：

Memo.Lines.LoadFromFile(FileName, TEncoding.ASCII);

代码1：

var

  LoadString: AnsiString;

  FS: TFileStream;

begin

  FS := TFileStream.Create(FileName, fmOpenRead or fmShareDenyNone);

  try

    SetLength(LoadString, FS.Size);

    FS.ReadBuffer(Pointer(LoadString)^, FS.Size);

  finally

    FS.Free;

  end;

  Memo.Lines.Add(String(LoadString));

end;

代码2：

uses

  System.Classes;

var

  LoadString: AnsiString;

  MS: TMemoryStream;

begin

  MS := TMemoryStream.Create;

  try

    MS.LoadFromFile(FileName);

    SetString(LoadString, PAnsiChar(MS.Memory), MS.Size);

  finally

    MS.Free;

  end;

  Memo.Lines.Add(String(LoadString));

end;

代码3：

uses

  System.Classes, System.SysUtils;

var

  LoadString: String;

  Reader: TStreamReader;

begin

  Reader := TStreamReader.Create(FileName, TEncoding.ANSI);

  try

    LoadString := Reader.ReadToEnd;

  finally

    Reader.Free;

  end;

  Memo.Lines.Add(LoadString);

end;

代码4：

uses

  System.IOUtils, System.SysUtils;

var

  LoadString: String;

begin

  LoadString := TFile.ReadAllText(FileName, TEncoding.ANSI);

  Memo.Lines.Add(LoadString);

end;