String concatenation behavior in C Sharp (C#)

Introduction

String concatenation lets you join two or more pieces of text into one. It helps build messages or combine words easily.

When you want to create a full sentence from separate words or phrases.

When you need to add a user's name into a greeting message.

When combining file paths or URLs from parts.

When building output that shows multiple values together.

Syntax

C Sharp (C#)

string result = string1 + string2;
// or
string result = string.Concat(string1, string2);

The + operator joins strings simply and clearly.

string.Concat is a method that also joins strings and can take many parts.

Examples

Joins two string literals into one.

C Sharp (C#)

string hello = "Hello, " + "world!";

Joins a variable with strings to make a greeting.

C Sharp (C#)

string name = "Alice";
string greeting = "Hi " + name + "!";

Uses string.Concat to join multiple strings.

C Sharp (C#)

string combined = string.Concat("C#", " ", "rocks!");

Sample Program

This program joins first and last names with a space using +. Then it creates a welcome message using string.Concat. It prints both results.

C Sharp (C#)

using System;

class Program
{
    static void Main()
    {
        string firstName = "John";
        string lastName = "Doe";
        string fullName = firstName + " " + lastName;

        Console.WriteLine("Full name: " + fullName);

        string message = string.Concat("Welcome, ", fullName, "!");
        Console.WriteLine(message);
    }
}

Important Notes

Using + for many strings repeatedly can be less efficient than StringBuilder for big tasks.

Strings in C# are immutable, so concatenation creates new strings each time.

Summary

String concatenation joins text pieces into one string.

You can use + operator or string.Concat method.

It is useful for building messages or combining data for display.