C# String Concatenation

String Concatenation

The + operator can be used between strings to combine them. This is called concatenation:

string firstName = "John ";
string lastName = "Doe";
string name = firstName + lastName;
Console.WriteLine(name);

Note that we have added a space after "John" to create a space between firstName and lastName on print.

You can also use the string.Concat() method to concatenate two strings:

string firstName = "John ";
string lastName = "Doe";
string name = string.Concat(firstName, lastName);
Console.WriteLine(name);

WARNING!

C# uses the + operator for both addition and concatenation.

Remember: Numbers are added. Strings are concatenated.

If you add two numbers, the result will be a number:

int x = 10;
int y = 20;
int z = x + y;  // z will be 30 (an integer/number)

If you add two strings, the result will be a string concatenation:

string x = "10";
string y = "20";
string z = x + y;  // z will be 1020 (a string)