Using JavaScript to manipulate HTML input (checkbox) elements via type instead of name

Question

I am implementing an HTML form with some checkbox input elements, and I want to have a Select All or DeSelect All button. However, I do not want to rely on the name

Answer 1

iterate through the form.elements collection and check .type == "checkbox".

var button = getSelectAllButtonInFormSomeHow();
/*all formelements have a reference to the form. And the form has an elements-collection.*/
var elements = button.form.elements;

for(var i = 0; i < elements.length;i++) {
    var input = elements[i];
    if (input.tagName == "input" && input.type == "checkbox") input.checked = true;
}