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ryan_sabarre

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delete a row in stringgrid

How can i delete a row in a stringgrid?
Avatar of ryan_sabarre
ryan_sabarre

ASKER

help me pls.
and also how to sort an specified field in a stringgrid
TheStringGrid.Rows.Delete(row_number);

For sorting, unless someone gives you a better solution, you'll have to implement some sorting algorithm over TheStringGrid.Rows and use the Exchange method of TheStringGrid.Rows for exchanging items during sort.

HTH,
F.

Avatar of kretzschmar
a sample for sorting, digged out

unit stringgridsort_u;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, Grids;

type
  TForm1 = class(TForm)
    StringGrid1: TStringGrid;
    Button1: TButton;
    CheckBox1: TCheckBox;
    procedure StringGrid1MouseDown(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
    procedure Button1Click(Sender: TObject);
    procedure StringGrid1DrawCell(Sender: TObject; ACol, ARow: Integer;
      Rect: TRect; State: TGridDrawState);
  private
    FSortedColIndex : Integer;
    FSortOrder      : Boolean;
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

Var AsIntegerFlag : Boolean;

Function SpecialSort(List: TStringList; Index1, Index2: Integer): Integer;
begin
  Result := 0;
  try
    case AsIntegerFlag of
      //AnsiSort
      False : If List[Index1] < List[Index2] then Result := -1
              else If List[Index1] > List[Index2] then Result := 1;
      //IntegerSort
      True  : If StrToInt(List[Index1]) < StrToInt(List[Index2]) then Result := -1
              else If StrToInt(List[Index1]) > StrToInt(List[Index2]) then Result := 1;
    end;
  except
    Result := 0;  //No Sort on Error;
  end;
end;

Procedure SortGrid(AGrid : TStringGrid; ColIndex : Integer; SortOrder : Boolean;
                   //Optional Parameters
                   UseCustomSort : Boolean = False;
                   CustomSortProc : TStringListSortCompare = Nil);
//SortOrder=true->Ascending,SortOrder=False->Descending
//first row is excluded from the sort
var
  SL : TStringList;
  ARow : TStringList;
  I  : Integer;
begin
  if (assigned(AGrid)) and
     (ColIndex > -1) and
     (ColIndex < AGrid.ColCount) then
  begin
     SL := TStringList.Create;
    try
      For I := 1 to AGrid.RowCount - 1 do
      begin
        ARow := TStringList.Create;
        ARow.Assign(AGrid.Rows[i]);
        SL.AddObject(AGrid.Cells[ColIndex,I],ARow);
      end;
      if useCustomSort and assigned(CustomSortProc) then
      try
        SL.CustomSort(CustomSortProc);  //Userdefined sort
      except
        raise;
      end
      else
        SL.Sorted := true; //AnsiCompareString
      Case SortOrder of
        True : For I := 0 to SL.Count - 1 do
                 if Assigned(SL.Objects[I]) then
                   AGrid.Rows[I+1].Assign(TStringList(SL.Objects[I]));
       False : For I := SL.Count - 1  downto 0 do
                 if Assigned(SL.Objects[I]) then
                   AGrid.Rows[AGrid.RowCount - I - 1].Assign(TStringList(SL.Objects[I]));
      end;
    finally
      for I := 0 to sl.count-1 do
        if Assigned(SL.Objects[I]) then
        begin
          TStringList(SL.Objects[I]).Free;
          SL.Objects[I] := Nil;
        end;
      sl.free;
    end;
  end;
end;

Function RandomString(Lngth : Integer; CharSet : TSysCharset) : String;
var C : Char;
begin
  Result := '';
  if (lngth > 0) and not (CharSet = []) then
    while length(Result) < lngth do
    begin
      Repeat
        C := Chr(Random(255));
      Until C in CharSet;
      Result := Result + C;
    end;
end;



procedure TForm1.StringGrid1MouseDown(Sender: TObject;
 Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
var
  ACol,ARow : Integer;
  ASortProc : TStringListSortCompare;
begin
  ASortProc := SpecialSort;
  StringGrid1.MouseToCell(x,y,ACol,ARow);
  AsIntegerFlag := ACol in [1,2];
  if (ARow = 0) and
     (ACol > 0) and
     (Acol < StringGrid1.RowCount) then
    if Button =  mbleft then
    begin
      FSortedColIndex := ACol;
      FSortOrder := True;
      SortGrid(StringGrid1,ACol,True,Checkbox1.Checked,ASortProc)  //asc on columntitle-leftclick
    end
    else
    begin
      FSortedColIndex := ACol;
      FSortOrder := False;
      SortGrid(StringGrid1,ACol,False,Checkbox1.Checked,ASortProc);//Desc on columntitle-rightclick
    end;
end;

//Create a unsorted content
procedure TForm1.Button1Click(Sender: TObject);
var I : Integer;
begin
  StringGrid1.RowCount := 10001;
  StringGrid1.ColCount := 7;
  for i := 1 to 6 do
    StringGrid1.Cells[I,0] := Randomstring(5,['0'..'9','A'..'Z','a'..'z']);
  for i := 1 to 10000 do  //10000 Rows
  begin
    StringGrid1.Cells[1,I] := IntToStr(I);
    StringGrid1.Cells[2,I] := IntToStr(10001-I);
    StringGrid1.Cells[3,I] := Randomstring(10,['A'..'Z']);
    StringGrid1.Cells[4,I] := Randomstring(10,['0'..'9','A'..'Z','a'..'z']);
    StringGrid1.Cells[5,I] := Randomstring(10,[#0..#255]);
    StringGrid1.Cells[6,I] := '1000';
  end;
end;

//Draw a Triangle additional to the Caption
procedure TForm1.StringGrid1DrawCell(Sender: TObject; ACol, ARow: Integer;
  Rect: TRect; State: TGridDrawState);
const CMargin = 5;
begin
  If (ARow = 0) and (ACol = FSortedColIndex) then  //FSortedColIndex->the col, which is sorted
  case FSortOrder of
    true : begin  //Ascending
             StringGrid1.Canvas.Pen.Color := clbtnShadow;
             StringGrid1.Canvas.MoveTo(Rect.Right-CMargin,Rect.Top+CMargin);
             StringGrid1.Canvas.LineTo(Rect.Right-7-CMargin,Rect.Top+CMargin);
             StringGrid1.Canvas.LineTo(Rect.Right-4-CMargin,Rect.Top+7+CMargin);
             StringGrid1.Canvas.Pen.Color := clBtnHighLight;
             StringGrid1.Canvas.LineTo(Rect.Right-CMargin,Rect.Top+CMargin);
           end;
   false : begin  //Descending
             StringGrid1.Canvas.Pen.Color := clBtnHighLight;
             StringGrid1.Canvas.MoveTo(Rect.Right-4-CMargin,Rect.Top+CMargin);
             StringGrid1.Canvas.LineTo(Rect.Right-CMargin,Rect.Top+7+CMargin);
             StringGrid1.Canvas.LineTo(Rect.Right-7-CMargin,Rect.Top+7+CMargin);
             StringGrid1.Canvas.Pen.Color := clbtnShadow;
             StringGrid1.Canvas.LineTo(Rect.Right-4-CMargin,Rect.Top+CMargin);
           end;
  end;
end;

initialization
  Randomize;
end.

meikl ;-)
HELP ME
please how to DELETE a row in a stringgrid

=fva= you gave me a wrong answer
      your code was not recognized
      delphi ask for '[' in Rows
      and you given me this one.
      TheStringGrid.Rows.Delete(row_number);
? maybe you should explain more
Deeply sorry. My fault. I didn't test the code, just wrote it directly. I'll try to find something better.

F.
its ok
ASKER CERTIFIED SOLUTION
Avatar of fva
fva

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thank you so so much fva
Don't mention it. Delete the other question with the same title and having 50 pts hanging. You'll get back the points and probably fast since no one commented it yet. Thank you for accepting my comments.

BTW, you should have requested in Community Support for a point split on this one instead of giving me 100 and posting another 50 for Meikl.

Yours,
F.
an old trick you can use is the protected DeleteRow method

i know this is already answered but i had this on the clipboard so ... ;-)

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  Grids, StdCtrls;

type
 TDelGrid = Class( TStringGrid);
  TForm1 = class(TForm)
    Button1: TButton;
    StringGrid1: TStringGrid;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.Button1Click(Sender: TObject);
begin
  with TDelGrid(StringGrid1) do
   DeleteRow( Stringgrid1.Row );
end;

end.
Hi inthe,

Just curious (2 issues):
1. Am I missing something here? (I'm in a D3 shop)
Looks like you didn't expose DeleteRow in TDelGrid definition.
and
2. How did you get to comment a PAQ (haven't seen you on the comment list)? I guess you didn't buy it just for that.

Cheers,
F.