javascript - 使用 JQuery 时为 ":last-of-type"或 ".last()"

Question

:last-of-type (as of v1.9)对比.last() (as of v1.4) : 这两种方法都有效，但谁能告诉我哪种方法基于效率更好？

示例:

$(".item").last();

$(".item:last-of-type");

".last()"的存在时间更长(从 v1.4 开始)。 JQuery 是否内置了“:last-of-type”，或者它只是利用 CSS 和搭载浏览器的功能？谁能证实这一点？

在我看来，如果是这种情况，“:last-of-type”在适用时会更好。

Answer 1

.last() 更快。

注意，选择器执行不同的选择

:last-of-type

last-of-type selector

Description: Selects all elements that are the last among siblings of the same element name.

.last()

.last()

Description: Reduce the set of matched elements to the final one in the set.

console.time("lastOfType");
$(".item:last-of-type");
console.timeEnd("lastOfType");

console.time("last");
$(".item").last();
console.timeEnd("last");

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