How to trim a string to N chars in Javascript?

Question

How can I, using Javascript, make a function that will trim string passed as argument, to a specified length, also passed as argument. For example:

var strin         


        

Answer 1

Copying Will's comment into an answer, because I found it useful:

var string = "this is a string";
var length = 20;
var trimmedString = string.length > length ? 
                    string.substring(0, length - 3) + "..." : 
                    string;

Thanks Will.

And a jsfiddle for anyone who cares https://jsfiddle.net/t354gw7e/ :)