EASYTUTORGUIDEC# • C# 14 on .NET 10 LTS

Methods

C# Chapter 10 of 60. Beginner-to-advanced teaching with a code example for every topic.

5 topics5 code examples10 Q&A

10.1 Declaring Methods

Declaring Methods is part of Methods. Learn what the construct does, the syntax it requires, how data moves through it, and the mistakes that can make the program incorrect or unsafe.

Why it matters

Use this feature when it makes the program clearer, safer, easier to maintain, or more efficient. Start with a small example before using it in a larger application.

Code example

static int Add(int a, int b) => a + b;
Console.WriteLine(Add(3, 4));

Step-by-step

  1. Read the declarations and identify each value or object.
  2. Follow execution from the first statement to the last.
  3. Predict the output before running the example.
  4. Run or compile it using the toolchain for this course.
  5. Change one input and explain why the new result changes.

Expected result

The example should demonstrate Declaring Methods with a small, inspectable result. For platform-dependent or advanced examples, focus on the API pattern and verify the exact environment requirements.

Common mistakes

Common mistakes include using the feature before understanding lifetime/scope, ignoring errors, assuming conversions are harmless, or writing code that works only for one happy-path input.

Practice

Rewrite the example with different data. Add one edge case, predict the result, then test it. Explain the feature in your own words without looking at the lesson.

10.2 Parameters

Parameters is part of Methods. Learn what the construct does, the syntax it requires, how data moves through it, and the mistakes that can make the program incorrect or unsafe.

Why it matters

Use this feature when it makes the program clearer, safer, easier to maintain, or more efficient. Start with a small example before using it in a larger application.

Code example

static int Add(int a, int b) => a + b;
Console.WriteLine(Add(3, 4));

Step-by-step

  1. Read the declarations and identify each value or object.
  2. Follow execution from the first statement to the last.
  3. Predict the output before running the example.
  4. Run or compile it using the toolchain for this course.
  5. Change one input and explain why the new result changes.

Expected result

The example should demonstrate Parameters with a small, inspectable result. For platform-dependent or advanced examples, focus on the API pattern and verify the exact environment requirements.

Common mistakes

Common mistakes include using the feature before understanding lifetime/scope, ignoring errors, assuming conversions are harmless, or writing code that works only for one happy-path input.

Practice

Rewrite the example with different data. Add one edge case, predict the result, then test it. Explain the feature in your own words without looking at the lesson.

10.3 Return Values

Return Values is part of Methods. Learn what the construct does, the syntax it requires, how data moves through it, and the mistakes that can make the program incorrect or unsafe.

Why it matters

Use this feature when it makes the program clearer, safer, easier to maintain, or more efficient. Start with a small example before using it in a larger application.

Code example

// Return Values
var value = 42;
Console.WriteLine($"Value = {value}");

Step-by-step

  1. Read the declarations and identify each value or object.
  2. Follow execution from the first statement to the last.
  3. Predict the output before running the example.
  4. Run or compile it using the toolchain for this course.
  5. Change one input and explain why the new result changes.

Expected result

The example should demonstrate Return Values with a small, inspectable result. For platform-dependent or advanced examples, focus on the API pattern and verify the exact environment requirements.

Common mistakes

Common mistakes include using the feature before understanding lifetime/scope, ignoring errors, assuming conversions are harmless, or writing code that works only for one happy-path input.

Practice

Rewrite the example with different data. Add one edge case, predict the result, then test it. Explain the feature in your own words without looking at the lesson.

10.4 Overloading

Overloading is part of Methods. Learn what the construct does, the syntax it requires, how data moves through it, and the mistakes that can make the program incorrect or unsafe.

Why it matters

Use this feature when it makes the program clearer, safer, easier to maintain, or more efficient. Start with a small example before using it in a larger application.

Code example

// Overloading
var value = 42;
Console.WriteLine($"Value = {value}");

Step-by-step

  1. Read the declarations and identify each value or object.
  2. Follow execution from the first statement to the last.
  3. Predict the output before running the example.
  4. Run or compile it using the toolchain for this course.
  5. Change one input and explain why the new result changes.

Expected result

The example should demonstrate Overloading with a small, inspectable result. For platform-dependent or advanced examples, focus on the API pattern and verify the exact environment requirements.

Common mistakes

Common mistakes include using the feature before understanding lifetime/scope, ignoring errors, assuming conversions are harmless, or writing code that works only for one happy-path input.

Practice

Rewrite the example with different data. Add one edge case, predict the result, then test it. Explain the feature in your own words without looking at the lesson.

10.5 Method Design

Method Design is part of Methods. Learn what the construct does, the syntax it requires, how data moves through it, and the mistakes that can make the program incorrect or unsafe.

Why it matters

Use this feature when it makes the program clearer, safer, easier to maintain, or more efficient. Start with a small example before using it in a larger application.

Code example

static int Add(int a, int b) => a + b;
Console.WriteLine(Add(3, 4));

Step-by-step

  1. Read the declarations and identify each value or object.
  2. Follow execution from the first statement to the last.
  3. Predict the output before running the example.
  4. Run or compile it using the toolchain for this course.
  5. Change one input and explain why the new result changes.

Expected result

The example should demonstrate Method Design with a small, inspectable result. For platform-dependent or advanced examples, focus on the API pattern and verify the exact environment requirements.

Common mistakes

Common mistakes include using the feature before understanding lifetime/scope, ignoring errors, assuming conversions are harmless, or writing code that works only for one happy-path input.

Practice

Rewrite the example with different data. Add one edge case, predict the result, then test it. Explain the feature in your own words without looking at the lesson.

10 Questions & Answers

1. What should you understand about Declaring Methods?

Know its purpose, syntax, input/output behavior, edge cases, and the main safety or maintainability concern.

2. What should you understand about Parameters?

Know its purpose, syntax, input/output behavior, edge cases, and the main safety or maintainability concern.

3. What should you understand about Return Values?

Know its purpose, syntax, input/output behavior, edge cases, and the main safety or maintainability concern.

4. What should you understand about Overloading?

Know its purpose, syntax, input/output behavior, edge cases, and the main safety or maintainability concern.

5. What should you understand about Method Design?

Know its purpose, syntax, input/output behavior, edge cases, and the main safety or maintainability concern.

6. What should you understand about Declaring Methods?

Know its purpose, syntax, input/output behavior, edge cases, and the main safety or maintainability concern.

7. What should you understand about Parameters?

Know its purpose, syntax, input/output behavior, edge cases, and the main safety or maintainability concern.

8. What should you understand about Return Values?

Know its purpose, syntax, input/output behavior, edge cases, and the main safety or maintainability concern.

9. What should you understand about Overloading?

Know its purpose, syntax, input/output behavior, edge cases, and the main safety or maintainability concern.

10. What should you understand about Method Design?

Know its purpose, syntax, input/output behavior, edge cases, and the main safety or maintainability concern.