Form1 Scientific Calculator Form1% Operand1Box OperatorBox Operand2Box ResultBox ErrorMessageBox ExecuteBtn Execute QuitBtn StoreBtn Store VariableBox Operand1Lbl Operand 1 OperatorLbl Operator Operand2Lbl Operand 2 ResultLbl Result ErrorMessageLbl Error Message VariableLbl Variable Command2_Click QuitBtn_Click StoreBtn_Click VariableBox ErrorMessageBox Index ResultBox ResultBox_Change OperatorBox_Change Operand2Box_Change Operand1Box_ChangeD Label6_ClickT Label5_Clickd Label4_Clickt Label3_Click Label2_Click Label1_Click Form_Click ExecuteBtn_Click, ErrorMessageBox_Change Operand1Box Operand2Box+ OperatorBox ErrorFlag Xchar YChar= Cchar VariableBox_Changep ErrorMesageBox{ ASCII_A TheVars InvalidY False InValifY ErrorMsesageBox ErrorMes sageBox IfEnd ErroressageBox InValid| numeric operand5 displayJ Operand1Lbl_Click_ Operand2Lbl_Click OperatorLbl_ClickL ErrorMessageLbl_Click OperatorBox_DragDrop Source_ OperatorBox_DragOver State OperatorBox_GotFocus OperatorBox_KeyDown KeyCode7 Shift OperatorBox_KeyPress KeyAscii OperatorBox_KeyUp ResultLbl_Clicki Op1Strs Op2Str OpStr Form1 Form_Load" ErrorMessageLbl_Click ExecuteBtn_Click clear error message box clear result boxa obtain the uppercase of the first character in thet Operand1Box text boxb obtain the uppercase of the first character in thet Operand2Box text boxb convert string in Operand1Box text box to its numeric value. Note that if the conversion fails,l X will be assigned a zero.i is X = 0 when Xchar is not "0"? This test detects failed conversionsr Yes! Is Xchar in the range A to Zh treat the content of Operand1Box as storing the name of a variable. Assign the value ofa the variable to X convert text in Operand2Box to numeric valuea check if Operand2Box has a variable Yes! there is a variable. Assign its value to variable Y examine the content of the OperatorBox text box Division by zero error simply copy the value of the firsts operand into the result box Bad function argument Bad function argument Bad function argument Invalid operator if the error message box is still empty, there is no error. Therefore, convert the variable Z into a string and display it in ResultBoxr Label3_Click get the uppercase of the first characterin the Operand2BoxB is the character in the range A to Z? Yes! Obtain the variable from the array and writew its numeric value to the text box Label5_Click clear the error message text boxb Operand1Lbl_Click get the uppercase of the first character in the Operand1Box is the character in the range A to Z? Yes! Obtain the variable from the array and writew its numeric value to the text box Operand2Lbl_Click get the uppercase of the first character in the Operand2Box is the character in the range A to Z? Yes! Obtain the variable from the array and writer its numeric value to the text box QuitBtn_Click StoreBtn_Click process the contents of the Variable text box obtain the upeprcase of the first character in the text box is the character in the range A to Z? Yes! Get the ASCII code for the character store the value of the Result box in the array TheVars# clear the error message box No! The text box has an invalid variable name Invalid variable name the text box is empty!n Missing variable name