Question

var b = document.getElementsByName("button");
var l = document.getElementsByName("link");

Which is the best way to add the content of these two arrays into one?
I don’t want to use for loop

Answer 1

You can use Array.prototype.slice.call() to turn the nodeLists into real arrays and then use array operations on them to combine them

var b = document.getElementsByName("button");
var l = document.getElementsByName("link");
// make both nodeLists into real arrays
var copyB = Array.prototype.slice.call(b, 0);
var copyL = Array.prototype.slice.call(l, 0);
var combined = copyB.concat(copyL);

Working demo: http://jsfiddle.net/jfriend00/vZ5tb/

Or, a little briefer version:

var copyB = Array.prototype.slice.call(document.getElementsByName("button"), 0);
var copyL = Array.prototype.slice.call(document.getElementsByName("link"), 0);
var combined = copyB.concat(copyL);