Problem Statement:

$We$ have a nearly completed calculator desktop application. However, the calculate method $is$ missing

the computation aspects $of$ the program, and $we$ need your help! Dive into the code, and add the

missing mathematical functionality. You will need $to$ only fix this portion $of$ the code.

Code tasks:

$1.$ Identify the $Calculate$ method within the code behind.

$2.$ ONLY MODIFY THIS METHOD!

$3.$ Complete the switch statement:

$a.$ Develop $4$ cases that will match the $currentOperation.$

$b.$ Use the two variables, $firstNumber$ and $secondNumber,$ found within the method.

$c.$ Display the result $to$ the $labelResult$ control.

$4.$ Optional: Find bugs within the program for brownie points.

Hints:

$*$ Use the debugger $to$ learn what variable inputs and outputs will $be!$

$*$ Place $an$ intelligent breakpoint $to$ stop the program where you need information

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Windows.Forms;

namespace Calculator

$\{$

public partial class Calc : Form

$\{$

private string currentNumber $=$ "Empty";

private string currentOperation $=$ "Blank";

public Calc$()$

$\{$

InitializeComponent$()$;

$\}$

private void ButtonNumber$\_$Click$($object sender$,$ EventArgs e$)$

$\{$

Button btn $=$ sender as Button;

if $($labelResult$.$Text $==$ "Enter Calculation" $||$ labelResult.Text $==$ "Syntax Error"$)//$ initial

$\{$

labelResult.Text $=$ btn$.$Text;

$\}$

else if $($labelResult$.$Text $=="/"||$ labelResult.Text $=="$x$"||$ labelResult.Text $=="-"||$ labelResult.Text $=="+")//$ handles number after operation

$\{$

labelResult.Text $=$ btn$.$Text;

$\}$

else if $($currentOperation $==$ "Blank" && currentNumber $==$ labelResult.Text$)//$ handles new number after enter click

$\{$

labelResult.Text $=$ btn$.$Text;

$\}$

else $//$ grow number

$\{$

labelResult.Text $=$ labelResult.Text $+$ btn$.$Text;

$\}$

$\}$

private void ButtonOperation$\_$Click$($object sender$,$ EventArgs e$)$

$\{$

Button btn $=$ sender as Button;

if $($labelResult$.$Text $==$ "Enter Calculation"$)//$ initial

$\{$

$//$ do nothing

return;

$\}$

else if $($currentOperation $==$ "Blank"$)//$ first operation

$\{$

currentNumber $=$ labelResult.Text;

$\}$

else

$\{$

$//$ calculate

ButtonEnter$\_$Click$($sender$,$ e$)$;

$\}$

currentOperation $=$ btn$.$Text;

labelResult.Text $=$ btn$.$Text;

$\}$

private void ButtonClear$\_$Click$($object sender$,$ EventArgs e$)//$ reset

$\{$

labelResult.Text $=$ "Enter Calculation";

currentNumber $=$ "Empty";

currentOperation $=$ "Blank";

$\}$

private void ButtonEnter$\_$Click$($object sender$,$ EventArgs e$)$

$\{$

if $($labelResult$.$Text $==$ currentOperation$)//$ handle case without second number

$\{$

labelResult.Text $=$ "Syntax Error";

currentNumber $=$ "Empty";

currentOperation $=$ "Blank";

return;

$\}$

Calculate$()$;

currentNumber $=$ labelResult.Text;

currentOperation $=$ "Blank";

$\}$

private void Calculate$()$

$\{$

string firstNumber $=$ currentNumber;

string secondNumber $=$ labelResult.Text;

switch $($currentOperation$)$

$\{$

$//$ case $1-$ perform division

$//$ case $2-$ perform multiplication

$//$ case $3-$ perform subtraction

$//$ case $4-$ perform addition

Enter Calculation

$8$

$9$

$4$

$5$

$6$

$1$

$3$

$+$

$0$ default: $//$ reset

ButtonClear$\_$Click$($null$,$ null$)$;

break;

$\}$

$\}$