When I Click a Button, and I want to chang a record's font color in DBGRID that i selected,I try to call ONDRAWDATACELL , the statement as following :

DBGrid1.Canvas.Font := clRed;
DBgrid1.OnDrawDataCell(DBGrid1,Rect,Field,State);

But I get a compiler error message :

[Error] srcUser0120.pas(343): There is no overloaded version of 'Rect' that can be called with these arguments

How can I call OnDrawDataCell when I click a Button?

根據Help文件
Do not write an OnDrawDataCell event handler. OnDrawDataCell is obsolete and included for backward compatibility. Instead, write an OnDrawColumnCell event handler.
的說法，請少用OnDrawDataCell。

您可改用OnDrawColumnCell，舉例如下
procedure TFORM1.DrawField(const Value : String;
const Rect : TRect;
vCanvas : TCanvas;
vFont: TFont;
vAlignment: TAlignment;
FontStyle : TFontStyles;
FontColor : TColor;
BGColor : TColor);
var
I : Integer;
begin
I := 0;
//First, fill in the background color of the cell
vCanvas.Brush.Color := BGColor;
vCanvas.FillRect(Rect);
//SetBkMode ensures that the background is transparent
SetBkMode(Canvas.Handle, TRANSPARENT);
//Set the passed font properties
vCanvas.Font := vFont;
vCanvas.Font.Color := FontColor;
vCanvas.Font.Style := vCanvas.Font.Style FontStyle;
//Set Text Alignment
case vAlignment of
taRightJustify :
begin
SetTextAlign(vCanvas.Handle, TA_RIGHT);
I := Rect.Right - 2;
end;
taLeftJustify :
begin
SetTextAlign(vCanvas.Handle, TA_LEFT);
I := Rect.Left 2;
end;
taCenter :
begin
SetTextAlign(vCanvas.Handle, TA_CENTER);
I := (Rect.Right Rect.Left) DIV 2;
end;
end; { case }
//Draw the text
vCanvas.TextRect(Rect, I, Rect.Top 2, Value);
SetTextAlign(vCanvas.Handle, TA_LEFT);
end;
procedure TFORM1.DBGrid1DrawColumnCell(Sender: TObject;
const Rect: TRect; DataCol: Integer; Column: TColumn;
State: TGridDrawState);
begin
inherited;
with Sender as TDBGrid, DataSource.DataSet do
begin
if QtabR_AM.AsInteger =0 then // 紫
DrawField(Column.Field.DisplayText, Rect, Canvas,
Column.Font, Column.Alignment, [fsBold],
clPurple,$00D2D2FF)
else
if Qtab_t65.AsFloat >1.3 then // 紅字
DrawField(Column.Field.DisplayText, Rect, Canvas,
Column.Font, Column.Alignment, [fsBold],
clRed, $00D2D2FF)
else
if Qtab_t65.AsFloat <0.7 then //橄欖 綠
DrawField(Column.Field.DisplayText, Rect, Canvas,
Column.Font, Column.Alignment, [fsBold],
clOlive,$00D2D2FF)
end;
end;

===================引 用 ken.hsueh 文 章===================
When I Click a Button, and I want to chang a record's font color in DBGRID that i selected,I try to call ONDRAWDATACELL , the statement as following :

DBGrid1.Canvas.Font := clRed;
DBgrid1.OnDrawDataCell(DBGrid1,Rect,Field,State);

But I get a compiler error message :

[Error] srcUser0120.pas(343): There is no overloaded version of 'Rect' that can be called with these arguments

How can I call OnDrawDataCell when I click a Button?

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