Quickest way would be with some regex:
Where n is the number
n.replace(/(\d{3})(\d{3})(\d{4})/, "$1-$2-$3");
Example: http://jsfiddle.net/jasongennaro/yXD7g/
var n = "1234567899";
console.log(n.replace(/(\d{3})(\d{3})(\d{4})/, "$1-$2-$3"));Quickest way would be with some regex:
Where n is the number
n.replace(/(\d{3})(\d{3})(\d{4})/, "$1-$2-$3");
Example: http://jsfiddle.net/jasongennaro/yXD7g/
var n = "1234567899";
console.log(n.replace(/(\d{3})(\d{3})(\d{4})/, "$1-$2-$3"));