Reading txt file with multiple columns to insert in Tlistview

Question

I have the following function:

var
   Colunas : TStringlist;
   Item: TListItem;
begin
   Colunas := TStringlist.Create;
   Colunas.Text := StringReplace('00:46:30@21/08/2014@Carlos dos Santos@São Paulo',
      '@',Char(13)+Char(10),[rfReplaceAll]);
   Item := LV.Items.Add;
   Item.SubItems.Add(Colunas[0]);
   Item.SubItems.Add(Colunas[1]);
   Item.SubItems.Add(Colunas[2]);

It separates by columns using the @delimiter, in this case I put manually. But, I have a file called client.txt and within it there are several lines of the type:

00:46:30@21/08/2014@Carlos dos Santos@são Paulo
00:46:30@21/08/2014@João da Silva@são Paulo

How can I read this file, using this same function above and put everything inside a LISTVIEW ?

_{Related: Explodes in Delphi}

Answer 1

I was based on a reply from Sozão to propose a way to read a file directly in a TStringlist, because the list can already be accessed "exploded" (using indexes).

var
  Linhas: TStringList;    

...

  Linhas := TStringList.Create;
  try
    Linhas.LoadFromFile(FileName);
    //Agora basta acessar as linhas com Linhas[0], Linhas[1], ..., Linhas[Linhas.Count-1]

  finally
    Linhas.Free;
  end;

Applying the solution to your . txt:

var
  Linhas:  TStringList;
  Colunas: TStringList;
  i:       integer;    

...

  Linhas := TStringList.Create;
  Colunas := TStringlist.Create;
  Colunas.Delimiter := '@';
  Colunas.StrictDelimiter := True;

  try
    Linhas.LoadFromFile( 'cliente.txt' );

    for i := 0 to Linhas.Count-1 do 
    begin
       Colunas.DelimitedText := Linhas[i];
       Item := LV.Items.Add;
       Item.SubItems.Add(Colunas[0]);
       Item.SubItems.Add(Colunas[1]);
       Item.SubItems.Add(Colunas[2]);
    end;

  finally
    Linhas.Free;
  end;

As well pointed out by @Edgar Muniz Berlinck, the code has been improved by using Tstringlist’s own feature to "explode" the string (and improved with the help of @Caputo, which recalled the Strictdelimiter of the D2006+):

We exchanged:

       Colunas.Text := StringReplace(Linhas[i],'@',Char(13)+Char(10),[rfReplaceAll]);

For:

       Colunas.Delimiter := '@';
       Colunas.StrictDelimiter := True;
       ...
       Colunas.DelimitedText := Linhas[i];

Answer 2

.You can use the following code to do this.

That way it gets more elegant is efficient.

procedure TForm1.Button1Click(Sender: TObject);
var
  Coluna, Linha: string;
  Colunas: TArray<string>;
begin
  Linha:= '00:46:30@21/08/2014@João da Silva@São Paulo';

  Colunas:= Linha.Split( [ '@' ] );

  for Coluna in Colunas do
    ShowMessage( Coluna );
end;

The Split is a Helper of the data type string. http://docwiki.embarcadero.com/Libraries/XE3/en/System.SysUtils.TStringHelper.Split

There are other methods Helper in the data type string. Typo Ctrl + Espaço after the variable to see the other methods.