Annotating text in UIWebView

I am writing a app that has a UIWebView that displays a HTML5 page. I want to annotate some text on the web page and save it in SQLite database. The annotated text must be changed to a specific color as a visual effect开发者_StackOverflow社区.

Any suggestions that how can I select and get the text back in Objective-C?

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You have two choices:

1. Parse the HTML5 document by hand
2. Inject Javascript into the page and walk the document. See Search and highlight text in UIWebView