Get the highest and lowest values of a certain attribute in jQuery or Javascript

Question

I have the following divs:

test
test


        
      

Answer 1

function minMaxId(selector) {
  var min=null, max=null;
  $(selector).each(function() {
    var id = parseInt(this.id, 10);
    if ((min===null) || (id < min)) { min = id; }
    if ((max===null) || (id > max)) { max = id; }
  });
  return {min:min, max:max};
}

minMaxId('div'); // => {min:1, max:5}

http://jsfiddle.net/qQvVQ/