Strings

In JavaScript and TypeScript, strings are represented by the string type and are immutable sequences of characters. Strings are defined using single ('), double ("), or backtick (``) quotes, with backticks enabling template literals for interpolation (e.g., `Hello, ${name}!`). There is no distinct char type; single characters are simply strings of length one (const letter: string = 'A';).

C# also has an immutable string type, which is a sequence of UTF-16 characters. Strings are defined using double quotes (string message = "Hello";) and support interpolation with $ ($"Hello, {name}!"). Unlike JavaScript, C# has a distinct char type for single characters (char letter = 'A';), which uses single quotes and represents a single UTF-16 character rather than a string. This distinction is important because char is a value type, while string is a reference type, impacting performance and memory usage.

Basics

let name = "Steve";
let name: string = "Steve";

var name = "Steve";
string name = "Steve";

TIP

In C#, the '' is a designator for a char or character type (as opposed to "" for string types.).

• 'c' is the char type representation of c
• "c" is the string type representation of c

Multi Line

let html = `
  <div>
    <p>Hello!</p>
  </div>
`;

var html = """
  <div>
    <p>Hello!</p>
  </div>
  """; // Note the left alignment.

INFO

See more about C#'s multi-line literals.

Interpolation

let name = `${first} ${last}`;

let html = `
  <div>
    <p>${greeting}</p>
  </div>
`;

var name = $"{first} {last}";

var html = $"""
  <div>
    <p>{greeting}</p>
  </div>
  """;

Substrings

let name = "Juan";
let a = name.slice(0, 1) // J
let b = name.slice(0, 1) // J
let c = name.slice(-2, -1) // a
let d = name.slice(-2) // an
let e = name.slice(1,-2) // u

var name = "Juan";
var a = name[0..1]; // J
var b = name[..1]; // J
var c = name[^2]; // a
var d = name[^2..]; // an
var e = name[1..^2]; // u

INFO

Learn more about C# ranges and indices