You can clear the validation messages using a very simple jQuery selector:
"#< validatorElement > span.k-tooltip-validation"
Regarding your second question, I am afraid that this is not supported out of the box. The easiest solution would be to call the validate method
and hide the messages immediately after that. Alternatively you can use the _checkValidity method but please have in mind that this method is intended for internal usage. The method accepts a jQuery selector (input element) and returns an object containing boolean property called "valid".
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