Expresiones Lambda en C# .Net

Introduction

This tutorial will guide you through understanding and utilizing lambda expressions in C#. Lambda expressions are a concise way to represent anonymous methods, making your code cleaner and more efficient. This guide will help you grasp the concept and practical application of lambda expressions in .NET.

Step 1: Understanding Lambda Expressions

• Lambda expressions are used to create anonymous functions.

• They provide a way to pass behavior as a parameter to methods.

• A typical lambda expression syntax is as follows:

  (parameters) => expression
  

• Example:

  x => x * x
  

  This expression takes an integer x and returns its square.

Step 2: Using Lambda Expressions with Collections

• Lambda expressions are often used with LINQ (Language Integrated Query) for querying collections.

• Example of using a lambda expression with a list:

  List<int> numbers = new List<int> { 1, 2, 3, 4, 5 };
  var squares = numbers.Select(x => x * x).ToList();
  

• In this example, Select uses a lambda expression to return the squares of the numbers in the list.

Step 3: Filtering Collections with Lambda Expressions

• You can filter collections using the Where method in combination with lambda expressions.

• Example:

  var evenNumbers = numbers.Where(x => x % 2 == 0).ToList();
  

• This filters the list to include only even numbers.

Step 4: Implementing Lambda Expressions in Custom Methods

• You can define methods that accept lambda expressions as parameters:

  public void ProcessNumbers(List<int> numbers, Func<int, int> operation)
  {
      foreach (var number in numbers)
      {
          Console.WriteLine(operation(number));
      }
  }
  

• Call the method using a lambda expression:

  ProcessNumbers(numbers, x => x + 10);
  

Step 5: Common Pitfalls to Avoid

• Ensure that the lambda expression matches the expected delegate type.
• Avoid overly complex expressions for readability.
• Remember that lambda expressions can capture variables from their enclosing scope, be cautious of unintended side effects.

Conclusion

Lambda expressions in C# offer a powerful way to write cleaner and more efficient code. They are particularly useful in LINQ for querying and manipulating collections. By following the steps outlined in this tutorial, you will be able to effectively implement lambda expressions in your applications. For further learning, explore more complex scenarios and practice with various collections and methods.