Area: Optimizely Add-ons
Applies to versions: 4

Forms 4 - Breaking changes

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Note: Optimizely Forms is supported by MVC-based websites only.

This topic describes the breaking changes for Optimizely Forms 4.0 in relation to the previous major version (3). To view the complete list of changes (marked with BREAKING in the title), see the release notes.


This release implements a feature request to support validation of multiple elements at once.

  • When a visitor clicks Submit and has JavaScript enabled, all elements are validated at once (except Captcha, because it needs server-side validation).

  • In non-JS mode, all elements are validated at once. New behaviors in this release:

    • Validation messages displayed on each failed element

    • Input data on the forms is not cleared

  • On server side, this function:


     processes all elements at once, and returns the array of ValidationInfo.

Breaking changes in Forms 4.0

interface IValidationService:

  • ValidateFormData(NameValueCollection formData, out ValidationInfo validationFailInfo) is marked with [Obsolete].

  • Add ValidateFormData(NameValueCollection formData, out IEnumerable<ValidationInfo> validationFailInfo).

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Last updated: Nov 02, 2016

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