请问大侠们，如何通过CMarkup在一个XML文档中定位节点和修改节点属性？

[unicode]

例如：我要找到下面例子的第8个line元素，并把内容改为：“12345678”

<?xml version="1.0" standalone="no"?>

<sonnet type="Shakespearean">
<author>
<last-name>Shakespeare</last-name>
<first-name>William</first-name>
<nationality>British</nationality>
<year-of-birth>1564</year-of-birth>
<year-of-death>1616</year-of-death>
</author>
<title>Sonnet 130</title>
<lines>
<line>My mistress' eyes are nothing like the sun,</line>
<line>Coral is far more red than her lips red.</line>
<line>If snow be white, why then her breasts are dun,</line>
<line>If hairs be wires, black wires grow on her head.</line>
<line>I have seen roses damasked, red and white,</line>
<line>But no such roses see I in her cheeks.</line>
<line>And in some perfumes is there more delight</line>

<!--就是这行-->
<line>Than in the breath that from my mistress reeks.</line>

<line>I love to hear her speak, yet well I know</line>
<line>That music hath a far more pleasing sound.</line>
<line>I grant I never saw a goddess go,</line>
<line>My mistress when she walks, treads on the ground.</line>
<line>And yet, by Heaven, I think my love as rare</line>
<line>As any she belied with false compare.</line>
</lines>
</sonnet>

[吹泡泡的小猫]

使用MS的DOMAPI操作xml文件

[unicode]

关键是如果定位到第8行