Stringgrid in delphi

Question

I am trying to write code to calculate sum of all numbers from cells that form main diagonal of stringgrid but the result I get is just number I typed in bottom right cell. Here's my code:

procedure TForm1.Button1Click(Sender: TObject);
var
  i, j: Integer;
begin
  with StringGrid1 do
  begin
    RowCount := StrToInt(Edit1.Text);
    ColCount := StrtoInt(Edit2.Text);
    for i := 0 to RowCount - 1 do
      Cells[0, i] := IntToStr(i);
    for j := 0 to ColCount - 1 do
      Cells[j, 0] := IntToStr(j);
  end;
end;

procedure TForm1.Button2Click(Sender: TObject);
var
  i, j, s, z, n: Integer;
begin
  z := 0;
  with StringGrid1 do
  begin
    for i := 1 to RowCount - 1 do
      for j := 1 to ColCount - 1 do
        s := StrToInt(Cells[j, i]);

    for n := RowCount - 1 to ColCount - 1 do
      if i = j then
        z := z + s;

    Label1.Caption := IntToStr(z);
  end;
end;

end.

What am I missing ? Thanks in advance

you missed `begin` after `for j:=1 to colcount-1 do` and `end` after `z:=z+s;` , you will have to keep this block together. — bummi, May 08 '14 at 17:17
The debugger could have lead you to the source of this problem in mere minutes, even with your poorly formatted code. Why didn't you try that? Honestly. — Rob Kennedy, May 08 '14 at 18:25
Another issue with the code is that you are not using any exception handling in case the strtoint fails. Read up on 'try except'. — Johan, May 09 '14 at 09:20
Personally, I think handling exceptions is a little bit too much in each and every case, so I use strToIntDef(myValue, defaultValue); in most cases — ZioBit, Dec 12 '18 at 06:43

score 0 · Answer 1 · answered May 08 '14 at 17:39

Your are not summing up any values. If your columcount is equal to your rowcount, then your for loop will only run once, for your last item.

procedure TForm1.Button2Click(Sender: TObject);
var
  i, j, s, z, n: integer;
begin
  z:=0;
  for i:=1 to StringGrid1.rowcount-1 do
    for j:=1 to StringGrid1.colcount-1 do
      if i=j then 
      begin
        s:=strtoint(cells[j, i]);
        z:=z+s;
      end;
  Label1.Caption:=inttostr(z);
end;

Stringgrid in delphi

1 Answers1