String creation and literal types in C Sharp (C#) - Mini Project: Build & Apply

String creation and literal types

📖 Scenario: You are creating a simple program that stores and displays different types of strings. This is like writing notes with different styles and formats.

🎯 Goal: Build a C# program that creates strings using different literal types and then prints them.

📋 What You'll Learn

Create string variables using normal string literals

Create string variables using verbatim string literals

Create string variables using interpolated string literals

Print all the string variables

💡 Why This Matters

🌍 Real World

Handling strings in different formats is common when working with file paths, messages, and user input in software.

💼 Career

Understanding string literals and how to create them correctly is essential for writing clear and bug-free code in many programming jobs.

1

Create normal string literals

Create two string variables called greeting and farewell. Set greeting to the value "Hello, world!" and farewell to the value "Goodbye!".

C Sharp (C#)

// Create two string variables greeting and farewell with the exact values
// Your code here

Hint

Use double quotes to create normal string literals in C#.

2

Create verbatim string literal

Add a string variable called filePath and set it to the verbatim string literal @"C:\Users\Public\Documents".

C Sharp (C#)

string greeting = "Hello, world!";
string farewell = "Goodbye!";
// Add a verbatim string literal called filePath
// Your code here

Hint

Use the @ symbol before the string to create a verbatim string literal that treats backslashes as normal characters.

3

Create interpolated string literal

Add a string variable called message that uses an interpolated string literal to combine greeting and farewell with a space between them. Use the syntax $"{greeting} {farewell}".

C Sharp (C#)

string greeting = "Hello, world!";
string farewell = "Goodbye!";
string filePath = @"C:\Users\Public\Documents";
// Add an interpolated string literal called message
// Your code here

Hint

Use the $ symbol before the string and curly braces to insert variables inside the string.

4

Print all string variables

Write Console.WriteLine statements to print the values of greeting, farewell, filePath, and message each on its own line.

C Sharp (C#)

string greeting = "Hello, world!";
string farewell = "Goodbye!";
string filePath = @"C:\Users\Public\Documents";
string message = $"{greeting} {farewell}";
// Print all string variables
// Your code here

Hint

Use Console.WriteLine to print each string variable on its own line.

Practice

1. Which of the following correctly creates a string literal in C#?

easy

A. string s = `Hello World`;

B. string s = 'Hello World';

C. string s = Hello World;

D. string s = "Hello World";

Solution

1. Step 1: Understand string literal syntax in C#

   Strings in C# must be enclosed in double quotes (").

2. Step 2: Check each option for correct syntax

   string s = "Hello World"; uses double quotes correctly. string s = 'Hello World'; uses single quotes which are for characters, not strings. string s = Hello World; has no quotes, so it's invalid. string s = `Hello World`; uses backticks which are not valid string delimiters in C#.

3. Final Answer:

   string s = "Hello World"; -> Option D

4. Quick Check:

   Strings use double quotes = A [OK]

Hint: Strings always use double quotes in C# [OK]

Common Mistakes:

• Using single quotes for strings
• Omitting quotes around text
• Using backticks instead of quotes

2. Which of the following is the correct way to create a verbatim string literal in C#?

easy

A. string path = @"C:\Users\Admin";

B. string path = "C:\\Users\\Admin";

C. string path = 'C:\Users\Admin';

D. string path = `C:\Users\Admin`;

Solution

1. Step 1: Recall verbatim string syntax

   Verbatim strings start with @ and use double quotes, preserving backslashes as-is.

2. Step 2: Analyze each option

   string path = "C:\\Users\\Admin"; uses normal string with escaped backslashes. string path = @"C:\Users\Admin"; uses @ with double quotes correctly. string path = 'C:\Users\Admin'; uses single quotes which is invalid for strings. string path = `C:\Users\Admin`; uses backticks which are invalid.

3. Final Answer:

   string path = @"C:\Users\Admin"; -> Option A

4. Quick Check:

   Verbatim strings start with @ = A [OK]

Hint: Use @ before quotes for verbatim strings [OK]

Common Mistakes:

• Forgetting @ for verbatim strings
• Using single quotes for strings
• Not escaping backslashes in normal strings

3. What is the output of the following C# code?

string s = "Line1\nLine2";
Console.WriteLine(s);

medium

A. Line1\nLine2

B. Line1\n\nLine2

C. Line1
Line2

D. Line1 Line2

Solution

1. Step 1: Understand escape sequences in strings

   The sequence \n represents a newline character in C# strings.

2. Step 2: Predict output of Console.WriteLine

   The string "Line1\nLine2" will print as two lines: "Line1" on the first line and "Line2" on the second line.

3. Final Answer:

   Line1 Line2 -> Option C

4. Quick Check:

   \n creates new line = D [OK]

Hint: Escape \n prints new line in output [OK]

Common Mistakes:

• Printing \n literally instead of new line
• Confusing verbatim strings with normal strings
• Expecting spaces instead of new lines

4. Identify the error in this C# string declaration:

string s = @"Hello\nWorld";

medium

A. Escape sequences like \n are not processed in verbatim strings

B. No error, this is correct verbatim string

C. Backslash should be doubled as \\ in verbatim strings

D. Missing semicolon at the end

Solution

1. Step 1: Understand verbatim string behavior

   Verbatim strings treat backslashes literally and do not process escape sequences like \n.

2. Step 2: Analyze the given string

   The string @"Hello\nWorld" will contain the characters \ and n literally, not a newline.

3. Final Answer:

   Escape sequences like \n are not processed in verbatim strings -> Option A

4. Quick Check:

   Verbatim strings ignore escape sequences = B [OK]

Hint: Verbatim strings do not process escape sequences [OK]

Common Mistakes:

• Expecting \n to create new line in verbatim strings
• Doubling backslashes unnecessarily in verbatim strings
• Confusing normal and verbatim string rules

5. You want to create a string that contains the exact text:

C:\Users\Admin\Documents

Which of the following C# declarations will produce this exact string value?

hard

A. string path = "C:\Users\Admin\Documents";

B. string path = @"C:\Users\Admin\Documents";

C. string path = "C:\\Users\\Admin\\Documents";

D. string path = 'C:\Users\Admin\Documents';

Solution

1. Step 1: Understand how to represent backslashes in strings

   In normal strings, backslash is an escape character, so to represent one backslash, you must write \\.

2. Step 2: Check each option for resulting string

   string path = @"C:\Users\Admin\Documents"; uses verbatim string which preserves backslashes literally, producing the exact text with single backslashes. string path = 'C:\Users\Admin\Documents'; uses single quotes which is invalid for strings. string path = "C:\Users\Admin\Documents"; has single backslashes which are escape sequences and will produce the correct path string with single backslashes. string path = "C:\\Users\\Admin\\Documents"; doubles each backslash, resulting in double backslashes in the string, which is not the exact text.

3. Final Answer:

   string path = @"C:\Users\Admin\Documents"; -> Option B

4. Quick Check:

   Verbatim string preserves backslashes literally = D [OK]

Hint: Use verbatim string (@) to preserve backslashes literally [OK]

Common Mistakes:

• Using single quotes for strings
• Doubling backslashes unnecessarily in verbatim strings
• Confusing verbatim and normal string rules