How do I make the first letter of a string uppercase in JavaScript?

Question

How do I make the first letter of a string uppercase, but not change the case of any of the other letters?

For example:

• \"this is a test\"

Answer 1

There is a very simple way to implement it by replace. For ECMAScript 6:

'foo'.replace(/^./, str => str.toUpperCase())

Result:

'Foo'