Name: Lindsay Haley Assignment: Ch.6 case 9. Design Steps of the Program Development Life Cycle

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1 Name: Lindsay Haley Assignment: Ch.6 case 9 Design Steps of the Program Development Life Cycle Requirements Document Date Submitted: October 15, 2013 Application Title: Purpose: Program Procedures: Algorithms, Processing, and Conditions: Notes and Restrictions: Comments: Use Case Definition Lindsay s Savings Calculator The Savings Calculator Windows application will display the yearly value of a savings account with compounding interest. On the form, the user will input the principle dollar amount, interest rate, and years. The program will display the yearly value of a savings account with compounding interest. 1. The user must input a positive number for Principle, Interest Rate, and Years to calculate savings with compounded interest. 2. After entering numbers for Principle, Interest Rate, and Years, the user clicks the Calculate button. 3. The program enters a loop where it multiplies the Principle by 1 + (Interest Rate *.01) and outputs balance into a ListBox object until the count reaches Years The user may click on any item in the ListBox object 5. The program will display a Message Box with years to attain the balance the user selects and if they can purchase a $5000 gaming computer 6. A clear button will clear the user s input and results The user should be able to click an exit button to close the application. Designer must determine the design of the user interface, and the words and graphics used in the user interface. Form must include a photo of a computer and a ListBox object to output savings balances. 1. User opens the application 2. User enters Principle, Interest Rate, and Years 3. User clicks Calculate button 4. Program determines if value of Principle, Interest Rate, and Years the user entered is a positive number a. If true, proceeds to step 5 b. If false, prompts user to enter a positive number 5. Program calculates yearly savings balance, with compounding interest 6. Program displays yearly savings balance in a list box 7. User can select a yearly savings balance to determine if they have saved enough for a $5000 computer 8. Program will display message box stating number of years to achieve balance and whether that balance is enough to purchase a $5000 gaming computer 9. User can click the Clear button and then repeat steps User can terminate program by clicking Exit button 1

2 User Interface List of the Controls Control Type Control Name Property Value Description Label lblprinciple Text Enter Principle Label for Principle Label lblinterest Text Enter Interest Rate as % Label for Interest Rate Label lblyears Text Enter Number of Years Label for Years Textbox txtprinciple Place to enter principle amount Textbox txtinterest Place to enter interest rate Textbox txtyears Place to enter years ListBox lstyearworth Text Label lblgoal Text Goal: $5000 for a Gaming Computer White ListBox to display calculated yearly savings Label to display goal BackColor PictureBox piccpu Image Image of a computer Button btncalculate Text &Calculate Used to initiate calculation Button btnclear Text Clea&r Used to clear form Button btnexit Text E&xit Used to exit form 2

3 Event Planning Document Program Name: Savings Calculator Developer: Lindsay Haley Object: frmsavingscalculator Date: 10/15/13 Object Event Trigger Event Processing IF txtprinciple AND txtinterest AND txtyears are positive numbers THEN enter Do Until Loop, ending when count reaches txtyears + 1 o Multiply txtprinciple by 1 + (txtinterest *.01) o output result to lstyearworth btncalculate Click o add 1 to count o make result the new value for txtprinciple for next iteration of loop o re-enter loop lstyearworth is visible IF txtprinciple OR txtinterest OR txtyears is/are not a positive number, display error message btnclear Click Clear text in txtprinciple, txtinterest, txtyears Clear text property of lstyearworth Hide lstyearworth Move cursor to txtprinciple btnexit Click Close form lstyearworth Click (user selects an item in list) Message box displays number of years to achieve that balance and whether or not it is enough to purchase a $5000 gaming computer 3

4 Event Flowcharts btnconvertcurrency Begin lstyearworthitemsclear = Input: txtprinciple Input: txtinterest Input: txtyears False txtprinciple AND txtinterest AND txtyears are postive numbers Output: "Please input a positive number for Principle, Interest, and Years." intcount = 1 decresult = 0 decprinc = Convert.ToDecimal(txtPrinc iple.text) decint = Convert.ToDecimal(txtInt.T ext) decintdec = Convert.ToDecimal(.01 * decint) intcount > Convert.ToInt32(txtYears.T ext) False decresult = decprinc * (decintdec + 1) Output: lstyearworth.items.add(fo rmatcurrency(decresult)) intcount = intcount + 1 decprinc = decresult lstyearworthvisible = End 4

5 btnclear btnexit lstyearworth 5