Microsoft Visual C++/cli step by Step

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Microsoft Visual C++/CLI Step by Step

// Simplified test for now – assume there are 31 days in  

// every month :-) 

if (month >= 1 && month <= 12 && day >= 1 && day <= 31) 

{ 

    DisplayDate(year, month, day); 

} 

Console::WriteLine("\nThe end\n");

This code asks the user to enter a year, month, and day. If the date passes a simplified valida-

tion test, the date is displayed on the console. If the date is invalid, it is not displayed at all.

Note This if statement combines several tests by using the logical AND operator &&. 

As you learned in Chapter 3, “Variables and operators,” logical tests are performed 

from left to right. Testing stops as soon as the final outcome has been established. 

For example, if the month is 0, there is no point performing the other tests—the 

date is definitely invalid. This is known as short-circuit evaluation.

8. 

Build the application and fix any compiler errors that you might have.

9. 

Run the application. Type in valid numbers for the year, month, and day (for example, 2012, 7, 

and 22).

The application displays the messages shown in the following screen shot:

Observe that the application displays the date because it is valid. The message “The End” also 

appears at the end of the program.

10. 

Run the application again, but this time, type an invalid date (for example, 2012, 2, and 33). 

The application displays the messages shown in the following screen shot:

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