StringGrid and LoadFromCSVFile

[justnewbie]

Hi! I have a StringGrid and want to fill it from a csv file.

Code: Pascal  [Select][+][-]

1. procedure TForm1.Button1Click(Sender: TObject);
2. begin
3.     StringGrid1.LoadFromCSVFile('list.csv');
4. end;

I have a fixed row for title (see picture).
My problem is that when loading from the csv, the title row will be overwritten with the first line of the csv.
How can I "protect" the title row?

[wp]

LoadFromCSV has a lot of optional parameters:

Code: Pascal  [Select][+][-]

1.     procedure LoadFromCSVFile(AFilename: string; ADelimiter: Char=',';
2.       UseTitles: boolean=true; FromLine: Integer=0; SkipEmptyLines: Boolean=true);

Maybe setting "UseTitle := false" helps

[justnewbie]

LoadFromCSV has a lot of optional parameters:

Code: Pascal  [Select][+][-]

1.     procedure LoadFromCSVFile(AFilename: string; ADelimiter: Char=',';
2.       UseTitles: boolean=true; FromLine: Integer=0; SkipEmptyLines: Boolean=true);

Maybe setting "UseTitle := false" helps

Works, thank you! (But, it is strange. Default is TRUE. Logically it should have to be TRUE for displaying the title, not FALSE.)

An other question: can I insert a column (which shows the line numbers) during loading before the first csv column (First)?

[wp]

I think, "UseTitle" means "Write the first data line as a title line in row 0"

can I insert a column (which shows the line numbers) during loading before the first csv column (First)

I don't think that this is possible during loading because the csv reader begins at the very first column. Of course, after loading you can add a column:

Code: Pascal  [Select][+][-]

1.     procedure InsertColRow(IsColumn: boolean; index: integer);

Afterwards, the easiest way to generate numbers is by turning the Option goFixedRowNumbering on (AFTER loading). If the number column is too wide you can adapt its width by chaingig ColWidths[0].

In total:

Code: Pascal  [Select][+][-]

1.   StringGrid.LoadFromCSVFile(filename, ',', false, 0, true);
2.   StringGrid.InsertColRow(true, 0);
3.   StringGrid.Options := StringGrid.Options + [goFixedrowNumbering];
4.   StringGrid.ColWidths[0] := StringGrid.Canvas.TextWidth(IntToStr(StringGrid.RowCount) + 8;

[justnewbie]

"I think, "UseTitle" means "Write the first data line as a title line in row 0"
Yes, you are right!

The solution is not perfect, I got this, see picture grid.

Code: Pascal  [Select][+][-]

1. procedure TForm1.Button1Click(Sender: TObject);
2. var numOfLines: integer;
3. begin    
4.     StringGrid1.LoadFromCSVFile('list.csv',',',false);
5.     StringGrid1.InsertColRow(true,0);
6.     StringGrid1.Options := StringGrid1.Options + [goFixedrowNumbering];
7.     StringGrid1.ColWidths[0] := 100;
8.     numOfLines:=StringGrid1.RowCount-1;
9.     Button1.Caption:='Load list ('+IntToStr(numOfLines)+' records)';
10. end;

 
If I add this:

Code: Pascal  [Select][+][-]

1. StringGrid1.FixedCols:=1;

then I got grid1 picture.

[wp]

The solution is not perfect, I got this, see picture grid.

I did not test my solution. Please post your data file (or a similar one following the same specification), then I can have a closer look. Zip it because the forum software does not accept all file types. Use "Attachments and other options" to upload the file here.

[justnewbie]

OK, attached. So, I need the filled grid from csv and a very first column that contains the line numbers.
Doesn't matter if the line numbers column is fixed or not. Fixed is a bit better.

Also, how can I achieve that button caption do show the "Loading ..." text during the load process (the real list contains more than 100.000 lines)?
I tried the

Code: Pascal  [Select][+][-]

1. Button1.Caption:='Loading ...';
2. Button1.Update;

and

Code: Pascal  [Select][+][-]

1. Button1.Caption:='Loading ...';
2. Button1.Repaint;

but none of them was good.

[wp]

See attachment

[justnewbie]

See attachment

Fantastic solution, thank you very much! 
(Just one note: Button1.Refresh; did not work, but Application.ProcessMessages; worked perfectly.)

[justnewbie]

+Questions:
1./ How can I get BOLD font for the title row?
2./ Is it possible to automatically resize the StringGrid's width? If yes, how?

[wp]

The event OnPrepareCanvas is generated immediately before a cell is drawn. The canvas is already set up for painting, but you have a last chance to intercept. Just set the StringGrid.Canvas.Font.Style to [fsBold] if the row parameter is zero:

Code: Pascal  [Select][+][-]

1. procedure TForm1.StringGrid1PrepareCanvas(sender: TObject; aCol, aRow: Integer;
2.   aState: TGridDrawState);
3. begin
4.   if aRow = 0 then
5.     StringGrid1.Canvas.Font.Style := [fsBold];
6. end;

Maybe you did not notice: I applied the same technique in my example above in order to right-justify the number column.

If you want to learn more about the Lazarus grids have a look at http://wiki.lazarus.freepascal.org/Grids_Reference_Page

[justnewbie]

@wp: your help is really great, thank you!