Introduction
This is a form-based application called “Joe’s Automotive.” This application calculates charges for different types of automotive services. The form contains checkboxes for various services like oil changes, lube jobs, radiator flush, etc., and text boxes for entering the parts and labor costs. The form also has several output labels that display the total charges, tax, service and labor costs, etc.
It demonstrates the implementation of a basic application for a fictional auto repair shop that calculates the cost of various services and parts for a customer’s vehicle. The code makes use of Windows Forms to create a graphical user interface and allows the user to select from a range of services and enter the cost of parts and labor. The application then calculates the total cost of the services, including tax, and displays the result to the user. It also includes a feature to clear the input fields and reset the form, as well as an exit button to close the application.
See My Code
Joe’s Automotive CS and .NET: michellealzola/Joe-Automotive: Desktop Application developed with C# and .NET. The problem is taken from Starting out with Visual C#, 5th Edition by Tony Gaddis (github.com)
About the Code
The frmJoeAutomotive class has several methods that handle specific types of services and their respective charges. These methods are OilLubeCharges(), FlushCharges(), MiscCharges(), and OtherCharges().
OilLubeCharges() method calculates the charges for an oil change and a lube job. It checks if the checkboxes for each service are checked and adds the respective cost to the oilLubeCharges variable.
FlushCharges() method calculates the charges for a radiator flush and a transmission flush. It checks if the checkboxes for each service are checked and adds the respective cost to the flushCharges variable.
MiscCharges() method calculates the charges for an inspection, muffler replacement, and tire rotation. It checks if the checkboxes for each service are checked and adds the respective cost to the miscCharges variable.
OtherCharges() method calculates the charges for parts and labor. It checks if the values entered in the tboxParts and tboxLabor textboxes are valid doubles and adds them to the otherCharges variable. If the tboxParts value is valid, it also calculates the parts tax using the TaxCharges() method and displays it in the lblOutTax label.
TaxCharges() method calculates the tax on the parts cost using the PARTS_TAX constant and returns the tax amount.
TotalCharges() method calculates the total charges for all the services, parts, and labor by adding all the charges together.
The btnCalculate_Click() event handler method is called when the “Calculate” button is clicked. It calls the OilLubeCharges(), FlushCharges(), MiscCharges(), and OtherCharges() methods to calculate the individual charges and stores them in their respective variables. It then calculates the total service and labor charges and displays it in the lblOutServiceLabor label. It displays the parts cost in the lblOutParts label and the parts tax in the lblOutTax label. Finally, it calculates the total charges using the TotalCharges() method and displays it in the lblOutTotalFees label.
The btnClear_Click() event handler method is called when the “Clear” button is clicked. It clears all the checkboxes, textboxes, and labels.
The btnExit_Click() event handler method is called when the “Exit” button is clicked. It closes the form.
See the Desktop Application in Action
Challenges
There are several challenges that one might face while developing this app. Some of these challenges include:
- Designing the user interface: Developing an intuitive and user-friendly interface can be a challenging task, especially for someone who is new to Windows Forms programming. The designer has to consider the user experience, accessibility, and ease of use.
- Handling input validation: The app must validate the input data entered by the user to ensure that it is valid and meets the required criteria. For instance, the app should only accept numerical values for parts and labor costs and display an error message when an invalid input is detected.
- Handling exceptions: The app should also be able to handle exceptions that may occur during the execution of the code. For instance, if the user enters an invalid input, such as a string instead of a number, the app should gracefully handle the error and display a message to the user.
- Handling changes in requirements: As with any software development project, changes in requirements may occur during the development cycle. The developer must be able to adapt to these changes and modify the code accordingly.
- Testing: The app must be thoroughly tested to ensure that it functions as intended and produces the expected results. Testing can be time-consuming, especially if there are many use cases to consider.
Conclusion
The app is a simple implementation of a program that calculates charges for automotive services. The program takes input from the user and calculates the charges based on the services selected and the input provided. The code uses basic programming concepts such as conditional statements, user-defined functions, and variables to perform the necessary calculations. It is a well-structured and functional application that performs the intended calculations and provides the user with the output they need.
