Expression-bodied lambdas in C Sharp (C#)

Introduction

Expression-bodied lambdas let you write short functions in a simple, clean way using just one expression.

When you want to write a quick function that returns a value without many lines.

When you need to pass a small function as an argument to another method.

When you want to make your code easier to read by avoiding extra braces and return statements.

Syntax

C Sharp (C#)

(parameters) => expression

The expression after the arrow is the value returned automatically.

No need for curly braces or explicit return keyword for single expressions.

Examples

A lambda that takes one parameter x and returns x squared.

C Sharp (C#)

x => x * x

A lambda that takes two parameters and returns their sum.

C Sharp (C#)

(a, b) => a + b

A lambda with no parameters that returns the current date and time.

C Sharp (C#)

() => DateTime.Now

Sample Program

This program shows three expression-bodied lambdas: one to square a number, one to add two numbers, and one to return a greeting message.

C Sharp (C#)

using System;

class Program
{
    static void Main()
    {
        Func<int, int> square = x => x * x;
        Func<int, int, int> add = (a, b) => a + b;
        Func<string> greet = () => "Hello!";

        Console.WriteLine(square(5));
        Console.WriteLine(add(3, 4));
        Console.WriteLine(greet());
    }
}

Important Notes

Expression-bodied lambdas are great for simple logic but use regular lambdas with braces for multiple statements.

They help keep your code short and easy to read.

Summary

Expression-bodied lambdas use a single expression after the arrow to return a value.

They simplify writing short functions without braces or return statements.

Useful for quick, readable code especially when passing functions as arguments.