Detect IE in Javascript

Below function will return up to IE 10

function IE(v) {
  return RegExp('msie' + (!isNaN(v)?('\\s'+v):''), 'i').test(navigator.userAgent);
}


and for IE 11 follow the below method

if(navigator.userAgent.indexOf("rv:11")>0 && navigator.userAgent.indexOf("Trident")>0)
{
alert("IE 11")
}