概述
可以使用 jQuery 选择器通过 jQuery 选择元素。该函数返回元素或元素列表。
基本选择器
$("*") // All elements
$("div") // All <div> elements
$(".blue") // All elements with class=blue
$(".blue.red") // All elements with class=blue AND class=red
$(".blue,.red") // All elements with class=blue OR class=red
$("#headline") // The (first) element with id=headline
$("[href]") // All elements with an href attribute
$("[href='example.com']") // All elements with href=example.com
关系运算符
$("div span") // All <span>s that are descendants of a <div>
$("div > span") // All <span>s that are a direct child of a <div>
$("a ~ span") // All <span>s that are siblings following an <a>
$("a + span") // All <span>s that are immediately after an <a>