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WCAG 2.0 AA Compliance

Section 3.3.3

If an input error is automatically detected and suggestions for correction are known, then the suggestions are provided to the user, unless it would jeopardize the security or purpose of the content.

The best way to achieve this is to provide a Javascript alert window that notifies the user of bad input. This is effective because some users of assisted technology might be confused that the same page was reloaded again. However, this is not required.

The normal practice is to use server-side technology (such as PHP, CFML, etc.) to check for bad user input and then reload the form page with the previous content entered using proper labeling of the bad user input. Make sure you use proper <label> tags when describing the bad user input, and that you are offering suggestions on how to enter the correct input that your script needs.

One last suggestion (not required) is to add a few words to the <title> tag of the page, such as "Form Submission Invalid," since it will relay the title of the page to an impaired user first.


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