Userscripts, going through elements and testing attributes

Question

I'm kinda new to Userscripts and JavaScript in general, and I'm pretty lost.

Basically what I want to do is go through elements I got by using getElementsByClassName, get the data in the "name" attribute, see if it contains something and if so, change the class name to something else.

In pseudo-ish-code:

items = getElementsByClassName("item1");

for each item in items {
    if(item.attribute("name").contains("Hi"))
        item.attribute("class") = "item2";
}

If someone could give me some tips on how I could do this, that'd be awesome.

Answer 1

Try this:

// get all items with class 'item1'
var items = document.querySelectorAll('.item1');
var length = items.length;
for (var i = 0; i < length; i++) {
    // save reference to current item
    var item = items[i];
    // check if name contains 'Hi'
    if (item.getAttribute('name').indexOf('Hi') !== -1) {
        // update class
        item.className += ' item2';
    }
}

Demo: http://jsfiddle.net/vpetrychuk/9zBnn