Use: http://jsfiddle.net/xH79d/
var n = $("input[name^='card']").length;
var array = $("input[name^='card']");
for(i=0; i < n; i++) {
// use .eq() within a jQuery object to navigate it by Index
card_value = array.eq(i).attr('name'); // I'm assuming you wanted -name-
// otherwise it'd be .eq(i).val(); (if you wanted the text value)
alert(card_value);
}
?