append
<p>
<span class="s1">s1</span>
</p>
<script>
$("p").append('<span class="s2">s2</span>');
</script>
结果是这样的:
<p>
<span class="s1">s1</span>
<span class="s2">s2</span>
</p>
after
<p>
<span class="s1">s1</span>
</p>
<script>
$("p").after('<span class="s2">s2</span>');
</script>
结果是这样的:
<p>
<span class="s1">s1</span>
</p>
<span class="s2">s2</span>
总结：
append/prepend 是在选择元素内部嵌入。
after/before 是在元素外面追加。