第一部分，当您创建HTMLNode时，它将遵循HTML的DTD，这就是为什么它变成了小写字母。您可以针对此问题使用 .setAttributeNS（NS，key，value）和 .creatElementNS（）。

第二部分，没有得到你...

例子：
http://jsfiddle.net/N52Qa/

I'm using jQuery to create an XML document on the fly by utilizing the document.createElement function. This works great for creating the structure as I am able to utilize the .appendTo function to dynamically place the correct nodes in the proper order. The problem comes when I set the attributes of the elements I create. As soon as they are created, they are set to lowercase and never preserve their case. This is unacceptable because the attributes will not match their expected format downstream.

I have tried to create the XML document on the fly by concatenating strings but this will not work because of the way nodes can be nested.

Is there any way I can use the createElement approach that preserves the case of each attribute?

first part, as you are creating HTMLNode, it will follow the DTD of HTML, that's why it turned into lowercase. You can use .setAttributeNS(NS, key, value) and .creatElementNS() for this problem.

second part, didn't get you...

example: http://jsfiddle.net/N52Qa/