Chart 顯示曲線值

procedure DBChart1MouseMove(Sender: TObject;
  Shift: TShiftState; X, Y: Integer);
var
    I : Integer;
    AValueIndex : Integer;
    TmpSeies : TChartSeries;
    tmpX,tmpY:double;
begin
  for I := 0 to TDBChart(Sender).SeriesList.Count - 1 do
  begin
    TmpSeies := TDBChart(Sender).SeriesList.Items[I];
    if TmpSeies = Series1 then
    begin
      AValueIndex := Series1.GetCursorValueIndex;
      if AValueIndex > -1 then
      begin
        Series1.GetCursorValues(tmpX,tmpY);  { <-- get values under mouse cursor }
        DBChart1.Canvas.Font.Color:=clRed;//字體顏色
        DBChart1.Canvas.Font.Size := 14;
        DBChart1.Canvas.Brush.Style := bsClear;//透明
        DBChart1.Canvas.TextOut(x+5,y-25,Series1.GetVertAxis.LabelValue(tmpY));
      end
      else
      DBChart1.Repaint;
    end;
  end;
end;

完善一部分功能

procedure  DBChart1MouseMove(Sender: TObject;
  Shift: TShiftState; X, Y: Integer);
  { This procedure draws the crosshair lines }
  Procedure DrawCross(AX,AY:Integer);
  begin
    With DBChart1,Canvas do
    begin
      Pen.Color:=CrossHairColor;
      Pen.Style:=CrossHairStyle;
      Pen.Mode:=pmXor;
      Pen.Width:=1;
      MoveTo(ax,ChartRect.Top-Height3D);
      LineTo(ax,ChartRect.Bottom-Height3D);
//      MoveTo(ChartRect.Left+Width3D,ay);
//      LineTo(ChartRect.Right+Width3D,ay);
    end;
  end;
var
    I : Integer;
    Vx : Double;
    AValueIndex : Integer;
    TmpSeies : TChartSeries;
    tmpX,tmpY,xpox:double;
begin
  DBChart1.Repaint;
  if (OldX<>-1) then
  begin
    DrawCross(OldX,OldY);  { draw old crosshair }
    OldX:=-1;
  end;

  { check if mouse is inside Chart rectangle }
  if PtInRect( DBChart1.ChartRect, Point(X-DBChart1.Width3D,Y+DBChart1.Height3D)  ) then
  begin
    DrawCross(x,y);  { draw crosshair at current position }
    { store old position }
    OldX:=x;
    OldY:=y;

    Series1.GetCursorValues(tmpX,tmpY);  { <-- get values under mouse cursor }
    if tmpX > 0 then
    begin
      DBChart1.Canvas.Font.Color:=clRed;//字體顏色
      DBChart1.Canvas.Font.Size := 14;
      DBChart1.Canvas.Brush.Style := bsClear;//透明
      Vx := Series1.YValues.Value[Trunc(tmpx)];
      DBChart1.Canvas.TextOut(x+5,y-25,FloatToStr(Vx));
    end;
  end;
end;