Get href attribute of a tag with id using XPath

Question

How do I get the Xpath that returns:

//www.example.com

With the following DOM:

<a id="myId" href="//www.example.com">
Click here</a>

Answer 1

//a[@id='myId']/@href

那应该可行，只要将其实现为使用xpath的任何语言即可。