How can we restrict accents and special character input in the standard fields or UDFs?

Summary:

We want to restrict the candidates to input accents (à, è, ì, ò, ù, À, È, Ì, Ò, Ù) or special characters ? Has anyone achieved this using any settings in the application or workarounds?

Content (please ensure you mask any confidential information):

Accent entries in first , middle or last name has caused lots of junk entries in the data base.

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Code Snippet (add any code snippets that support your topic, if applicable):