Using the SystemDrawing Namespace in C#

Generator Code 3/9 in C# Using the SystemDrawing Namespace

its place Did I mention the back peg Oh, yes, the inventor of cribbage was paranoid of cheating if you re unfamiliar with cribbage, you may want to check out the rules at wwwcribbageorg

To begin, create a playing surface I set up the board shown in Figure 5-2 without drawing the board itself I show you how to paint it on later with SystemDrawing My board looked a lot like Figure 5-3 when I was ready to start with the business rules

I used a little subroutine to handle score changes by calling it from the two text boxes OnChange events Here s the code that calls the subroutine:

private { try void HandleScore(TextBox scoreBox, Label points, Label otherPlayer) { if (0 > (int)scoreBoxText | (int)scoreBoxText > 27) { ScoreCheckSetError(scoreBox, Score must be between 0 and 27 ); scoreBoxFocus(); }

}

else { ScoreCheckSetError(scoreBox, ); //Add the score written to the points pointsText = (int)pointsText + (int)scoreBoxText; } } catch (SystemInvalidCastException ext) { //Something other than a number if (scoreBoxTextLength > 0) { ScoreCheckSetError(scoreBox, Score must be a number ); } } catch (Exception ex) { //Eek! MessageBoxShow( Something went wrong! + exMessage); } //Check the score if ((int)pointsText > 120) { if ((int)pointsText / (int)otherPlayerText > 15) { WinMessageText = scoreBoxNameSubstring(0, scoreBoxNameLength 6) + Skunked em!!! ; } else { WinMessageText = scoreBoxNameSubstring(0, scoreBoxNameLength 6) + Won!! ; } WinMessageVisible = true; }

All this changing of screen values causes the Paint event of the form to fire every time C# needs to change the look of a form for any reason, this event fires so I just tossed a little code in that event handler that would draw my board for me:

private void CribbageBoard_Paint(object sender, PaintEventArgs e) { PaintBoard(BillsPoints, GabriellesPoints); }

I need to paint right on a form to create the image of the board for my cribbage application, so I use the CreateGraphics method of the form control From there, I need to complete these tasks: Paint the board brown using a brush Draw six rows of little circles using a pen Fill in the hole if that is the right score Clean up my supplies

To that end, I came up with the PaintBoard method, which accepts the labels that contain the standing scores for both players It s shown in Listing 5-1

private void PaintBoard(ref Label Bill, ref Label Gabrielle) { Graphics palette = thisCreateGraphics; SolidBrush brownBrush = new SolidBrush(ColorBrown); paletteFillRectangle(brownBrush, new Rectangle(20, 20, 820, 180)); //OK, now I need to paint the little holes //There are 244 little holes in the board //Three rows of 40 times two, with the little starts and stops on either end //Let s start with the 240 int rows = 0; int columns = 0; int scoreBeingDrawn = 0; Pen blackPen = new Pen(SystemDrawingColorBlack, 1); SolidBrush blackBrush = new SolidBrush(ColorBlack); SolidBrush redBrush = new SolidBrush(ColorRed); } //There are 6 rows, then, at 24 and 40, 80 and 100, then 140 and 160 for (rows = 40; rows <= 160; rows += 60) { //There are 40 columns They are every 20 for (columns = 40; columns <= 820; columns += 20) { //Calculate score being drawn scoreBeingDrawn = ((columns - 20) / 20) + ((((rows + 20) / 60) - 1) * 40); //Draw Bill //If score being drawn = bill fill, otherwise draw if (scoreBeingDrawn == (int)BillText) { paletteFillEllipse(blackBrush, columns - 2, rows - 2, 6, 6); } else if (scoreBeingDrawn == BillsLastTotal) { paletteFillEllipse(redBrush, columns - 2, rows - 2, 6, 6); } else { paletteDrawEllipse(blackPen, columns - 2, rows - 2, 4, 4); } //Draw Gabrielle //If score being drawn = Gabrielle fill, otherwise draw if (scoreBeingDrawn == (int)GabrielleText) { paletteFillEllipse(blackBrush, columns - 2, rows + 16, 6, 6); } else if (scoreBeingDrawn == GabriellesLastTotal) { paletteFillEllipse(redBrush, columns - 2, rows + 16, 6, 6); } else { paletteDrawEllipse(blackPen, columns - 2, rows + 16, 4, 4); } } } paletteDispose(); brownBrushDispose(); blackPenDispose();