CD Publisher

In this exercise, we will develop an application for a small CD publishing company. The owner wants the prices to be calculated so a customer would get a discount if he orders more. To attract customers and encourage them to order more, she has decided to fix the prices so that the customer would pay:

• $20/CD if he orders less than 20 units
• $15/CD if he orders less than 50 units
• $12/CD if he orders less than 100 units
• $8/CD if he orders less than 500 units
• $5/CD if he orders more than 500 units

1. Start Visual Studio
2. Create a new Visual C# Windows Application and name it CDPublisher
3. Design the form as follows:
    

   Control Name Text Other Properties Label   Number of CDs:   NumericUpDown updQuantity   Maximum: 10000 TextAlign: Center Label   Unit Price:   TextBox txtUnitPrice 0 TextAlign: Right Label   Total Price:   TextBox txtTotalPrice 0 TextAlign: Right Button btnClose Close

4. Double-click the Close button and implement it as follows:
    

   private void btnClose_Click(object sender, System.EventArgs e) { Close(); }

5. Double-click the up down button to access its OnChange() event and implement it as follows:
    

   private void updQuantity_ValueChanged(object sender, System.EventArgs e) { int Quantity; double UnitPrice, TotalPrice; Quantity = Decimal.ToInt32(updQuantity.Value); if( Quantity < 20 ) UnitPrice = 20; else if( Quantity < 50 ) UnitPrice = 15; else if( Quantity < 100 ) UnitPrice = 12; else if( Quantity < 500 ) UnitPrice = 8; else UnitPrice = 5; TotalPrice = Quantity * UnitPrice; txtUnitPrice.Text = UnitPrice.ToString("C"); txtTotalPrice.Text = TotalPrice.ToString("C"); }

6. Test the application
7. Close it