What is the best way to load two text files into one TMemo component in Delphi?

Question

Let's say I have two text files (.txt) and I have a form with one TMemo Component on it. What would be the best way to quickly load both text files into the same Memo?

Answer 1

Use a TStringList to load each file and then use the AddStrings method to transfer the contents to the memo.

var
  Tmp: TStringList;
...
Memo1.Lines.BeginUpdate;
try
  Memo1.Lines.Clear;
  Tmp := TStringList.Create;
  try
    Tmp.LoadFromFile(FileName1);
    Memo1.Lines.AddStrings(Tmp);

    Tmp.LoadFromFile(FileName2);
    Memo1.Lines.AddStrings(Tmp);
  finally
    Tmp.Free;
  end;
finally
  Memo1.Lines.EndUpdate;
end;

In fact, this can easily be generalised to a potentially useful method like this:

procedure AppendMultipleTextFiles(Dest: TStrings; const FileNames: array of string);
var
  FileName: string;
  Tmp: TStringList;
begin
  Dest.BeginUpdate;
  try
    Tmp := TStringList.Create;
    try
      for FileName in FileNames do
      begin
        Tmp.LoadFromFile(FileName);
        Dest.AddStrings(Tmp);
      end;
    finally
      Tmp.Free;
    end;
  finally
    Dest.EndUpdate;
  end;
end;

You could then use the method like so:

Memo1.Lines.Clear;
AppendMultipleTextFiles(Memo1.Lines, [FileName1, FileName2]);