What is the best way to spellcheck form fields before submit?
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I'm trying to worn the users of spellcheck errors before they submit the form.
I'm looking for a solution that hopefully will highlight the misspelled word in an input, textarea or richtextarea(CKeditor) or at least give me a reference so I can highlight the field with the error in it.

I'm currently looking at www.javascriptspellcheck.com. I also saw www.webspellchecker.net but looks expensive.

Any other decent solutions maybe a server solution that I can query using ajax?

Thank you