delphi 文件的读取

procedure TForm_main.Button5Click(Sender: TObject);var  myStream:TFileStream;  myFileSize:Integer;  myTextFile:TextFile;  text,data,fileStr:string;  fileData:TStringList;  memory:TMemoryStream;  stringStream: TStringStream;  buffer:PChar;  resource:TResourceStream;  jj:TCustomMemoryStream;  MyWrite:TWriter;  MyReader:TReader;begin  //解析文件  普通读取  //myStream:=TFileStream.Create('');  AssignFile(myTextFile,Edit1.Text);  Reset(myTextFile);  while not Eof(myTextFile) do  begin    readln(myTextFile,text);    data:=data+text;    //ShowMessage(text);  end;  CloseFile(myTextFile);  //ShowMessage(data);  //TStringList 读取文件  fileData:=TStringList.Create;  fileData.LoadFromFile(Edit1.Text);  //ShowMessage('行数:'+inttostr(fileData.Count));  //Application.MessageBox(PWideChar(fileData.Text),'系统提示',0);  fileData.Free;  //TFileStream二进制读取  myStream:=TFileStream.Create(Edit1.Text,fmShareDenyRead);  myStream.Position:=0;  //myStream.Seek(0);  GetMem(buffer,myStream.Size);  //SetLength(buffer,myStream.Size);  myStream.Read(buffer^,myStream.Size);  ShowMessage(buffer);  fileStr:=Pchar(@buffer[0]);  ShowMessage(fileStr);   // TReader对应TWriter  //MyReader:=TReader.Create(myStream,myStream.Size); // filestr:=  MyReader.ReadString; // ShowMessage(fileStr);  FreeAndNil(myStream);  //  memory:=TMemoryStream.Create;  memory.LoadFromFile(Edit1.Text);  //memory.SaveToFile('test.txt');  memory.ReadBuffer(buffer^,memory.Size);  ShowMessage(memory.ToString);  ShowMessage(buffer);  //TStringStream读取文件  stringStream:=TStringStream.Create;  stringStream.LoadFromFile(Edit1.Text);  ShowMessage(stringStream.DataString);  stringStream.Free;end;