iframe spell check algorithm

I want to find the best way (using javascript) to check the spelling of an开发者_StackOverflow社区 iframe content based on the results that will be returned by the 'hunspell' spell checker.

• scan fast word by word the iframe content
• add a red underline style for each misspelled word that would work fast for the entire iframe content
• remove the spans when the user disabled spelling, etc