Problem 5 - C# Programming: From Problem Analysis to Program Design

Question

allows you to do the following: properly check the variable code to determine whether it contains the character \(C,\) and if it does, display "This … # Which statement in C# allows you to do the following: properly check the variable code to determine whether it contains the character \(C,\) and if it does, display "This is a check" and then advance to a new line? a. if code is equal to C Console.WriteLine("This is a check"); b. if (code = "C") Console.WriteLine("This is a check"); c. if (code == 'C') Console.WriteLine("This is a check"); d. if (code == C) Console.WriteLine("This is a check"); e. none of the above

Step-by-Step Solution

Answer

c. if (code == 'C') Console.WriteLine("This is a check");

Step 1: Understanding the Requirement

We need to write a conditional statement in C# that checks if a variable named 'code' contains the character 'C'. If it does, it should output "This is a check" and move to the next line using the Console.WriteLine method. We are given several options to choose from for the correct syntax.

Step 2: Analyzing Option A

Option A is written as: `if code is equal to C` `Console.WriteLine("This is a check");` This option uses 'is equal to', which is not correct C# syntax for comparison. It doesn’t use curly braces and uses a phrase instead of an operator. This makes it incorrect.

Step 3: Analyzing Option B

Option B is written as: `if (code = "C")` `Console.WriteLine("This is a check");` This option uses a single equals sign '=', which is the assignment operator in C#, not the equality operator. Also, it uses double quotes, which are for strings, not characters in C#.

Step 4: Analyzing Option C

Option C is written as: `if (code == 'C')` `Console.WriteLine("This is a check");` This option correctly uses the equality operator '==' for comparison and uses single quotes for the character 'C'. This syntax matches the C# requirement.

Step 5: Analyzing Option D

Option D is written as: `if (code == C)` `Console.WriteLine("This is a check");` This option makes a syntax error by not wrapping 'C' in quotes, which is necessary to identify it as a character in C#.

Step 6: Conclusion

Option C is the only one with correct syntax. It properly uses '==' to compare values and single quotes to specify a character. Therefore, the correct statement to use is: `if (code == 'C')` `Console.WriteLine("This is a check");`

Key Concepts

Understanding Conditional Statements in C#

Conditional statements in C# are building blocks that help execute code based on certain conditions. The most common conditional statement is the "if" statement. It evaluates a condition and executes a block of code if the condition is true. In our case, we check if a variable named 'code' contains the character 'C'.

To correctly employ a conditional statement, you must use the following syntax:

• Start with the keyword if
• Enclose your condition within parentheses ()
• Use the equality operator == for comparisons
• Use curly braces {} to define the block of code to execute

In our example, the statement if (code == 'C') checks if the variable 'code' holds the character 'C'. If true, the block inside the braces will execute.

Character Comparison in C#

Character comparison in C# involves checking if one character is equal to another. In C#, you use single quotes to denote characters. This is essential because it tells the language you are comparing characters and not strings.

When comparing characters, remember:

• Use single quotes ' ' for characters
• Use the equality operator == to check for equality
• Ensure the data types being compared are compatible

In our earlier example, code == 'C', the equality operator == checks if the variable 'code' contains the character 'C'. This comparison is case-sensitive, meaning 'C' is different from 'c'.

Understanding this distinction is crucial for accurate comparisons and correct program logic.

Using Console.WriteLine in C#

The method Console.WriteLine in C# is used to output text, numbers, or other data types to the console window. It is easy to use and effective for displaying messages or debugging information.

Key points about Console.WriteLine:

• Outputs a line of text followed by a newline character
• Can automatically convert data types to strings
• Accepts placeholders for variables in the form {0}, {1}, etc.

In the exercise statement Console.WriteLine("This is a check"), the method prints the string "This is a check" to the console and moves the cursor to a new line. This is beneficial for updating users or developers on program status, as it also helps separate output data neatly in a console application.