jQuery: Executing code for each element that matches a selector

Question

$("p") references all paragraphs on the current web page. Is it possible to execute code for each element that matched the selector?

Here's a simplistic example in pseudo-code:

// Show the background color of every paragraph on the page
foreach (object = $("p")) {
  alert(object.css("background-color"));
}

Answer 1

$('p').css('background-color', 'black')

If you need more flexibility:

$('p').each(function() {
    $(this).css('background-color', 'red');
});

Answer 2

You can use .each() for iterating through the matched elements, like this:

$("p").each(function() {
  alert($(this).css("background-color"));
});

If you want to set or do something (e.g. not getting a value from each like above), there's no need for .each(), just execute it and it'll run for every element on the set...this is the default jQuery behavior, for example:

$("p").show(); //shows all <p> elements