Pure JavaScript client side validation is the simplest but least feature-rich type of Client Side Validation. This type of validation uses 100% client-side JavaScript code to try to validate the values entered by the user. Because the validation logic is actually repeated in the JavaScript code, it is important to understand that some values will be considered acceptable by the JavaScript code but will be marked as unacceptable by the server-side Validation.
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JavaScript client validation is not available for visitor validations.
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Error reporting
Because client side validation does not talk to the server, the theme (xhtml theme or css_xhtml theme) is responsible for properly manipulating the HTML DOM to display the error message inline. The JavaScript that is responsible for doing this logic is validation.js and can be found in each theme.
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Errors are reported using the default validation message, not the internationalized version that the server-side might be aware of. This is a known issue. You may want to try the AJAX Client Side Validation for messages that are fully internationalized.
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Additional Validator Support
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