private void calc_KeyUp(object sender, KeyEventArgs e) { Keys keyCode = e.KeyCode; int keyValue = e.KeyValue; if (keyCode >= Keys.D0 && keyCode <= Keys.D9) { calculator.addDisplayNumber((keyValue - ((int)Keys.D0))); } else if (keyCode >= Keys.NumPad0 && keyCode <= Keys.NumPad9) { calculator.addDisplayNumber((keyValue - ((int)Keys.NumPad0))); } else if (keyCode == Keys.Delete) { calculator.removeDisplays(); } else if (keyCode == Keys.Back) { calculator.removeLastDisplayNumber(); } else if (keyCode == Keys.Add) { calculator.addOperator((char)Calculator.Symbols.ADD); } else if (keyCode == Keys.Subtract) { calculator.addOperator((char)Calculator.Symbols.SUBSTRACT); } else if (keyCode == Keys.Multiply) { calculator.addOperator((char)Calculator.Symbols.MULTIPLY); } else if (keyCode == Keys.Divide) { calculator.addOperator((char)Calculator.Symbols.DIVIDE); } else if (keyCode == Keys.Decimal || keyCode == Keys.Oemcomma) { calculator.appendDisplayComma(); } else if (keyCode == Keys.Return) { calculator.calculateResult(); } printDisplays(calculator.getDisplays()); }