- Access exercises (91)
- C# exercises (79)
- Excel exercises (278)
- Power Apps exercises (13)
- Power Automate exercises (18)
- Power BI exercises (139)
- Python exercises (28)
- Report Builder exercises (141)
- SQL exercises (198)
- SSAS exercises (51)
- SSIS exercises (46)
- SSRS exercises (99)
- VBA exercises (85)
- Visual Basic exercises (46)
VISUAL C# EXERCISES▼
- Creating forms (4)
- Coding form events (1)
- Laying out your code (2)
- C# variables (4)
- Enumerations and constants (2)
- Conditions (2)
- Modular code (3)
- Arrays (2)
- Looping (2)
- Files and folders (3)
- Properties in C# (3)
- Using lists (3)
- Validating forms (6)
- Toolbars, menus and status bars (1)
- FileDialogs and StreamReaders (1)
- Debugging and trapping errors (1)
- Introduction to DataGridViews (1)
- DataGridView events (3)
- Complex DataGridViews (2)
- Creating classes (4)
- The form as a class (1)
- Data structures (6)
- Inheritance (5)
- Interfaces (2)
- Delegates and events (2)
- Writing LINQ (2)
- Advanced LINQ (2)
- Entity Frameworks (1)
- LINQ with Entity Frameworks (4)
- Grouping using LINQ (2)
- LINQ to SQL (2)
Visual C# | Creating classes exercise | Use basic classes to create a shopping list app in C#
This exercise is provided to allow potential course delegates to choose the correct Wise Owl Microsoft training course, and may not be reproduced in whole or in part in any format without the prior written consent of Wise Owl.
You need a minimum screen resolution of about 700 pixels width to see our exercises. This is because they contain diagrams and tables which would not be viewable easily on a mobile phone or small laptop. Please use a larger tablet, notebook or desktop computer, or change your screen resolution settings.
In a new or existing project, create a new from called frmShoppingList to look like this:
Call the text boxes txtItem, txtUnit and txtAmount, and the listbox txtList.
First add code to the Cancel button (it should just close the form, which being the current object you can refer to as this).
Create a class called ShoppingList, and create 3 private fields to hold the 3 things being entered:
// private fields for each textbox
private string itemName;
private string unit;
private double amount;
Create one public property for each of these private fields, to expose the value of it to the world.
Attach code to the Add item button which will create a new instance of the ShoppingList class, and make it work (well, soon):
// can now create and add to list new item
ShoppingItem thing = new ShoppingItem();
// could use our amount property here
thing.Amount = Convert.ToDouble(txtAmount.Text);
thing.ItemName = txtItem.Text;
thing.Unit = txtUnit.Text;
thing = null;
You can assume that a user has typed in sensible things in each of the 3 text boxes, although the answer given does trap for this.
The only thing left now is to create the Add method for the ShoppingItem class. This should take a TextBox as an argument (hint: you may need to add an additional using statement at the top of your class).
Run your application and try adding a few items:
What the form might look like after adding 3 items.
Close down your application and all open files (don't worry about the fact that this loses your shopping list - you can always create another ...).