Web / Typescript interview questions
What does the question mark (?) on a typescript variable/parameter name denote?
Question mark on a typescript variable marks it as optional. Any optional parameters must follow required parameters.
function sayHello(name: string, salutation?: string) { if (salutation) return "Hello " + saluation +"." + name; else return "Hello " + name; }
The optional parameters will have value as undefined when unused.
More Related questions...
