Java script validating form

This means that we are able to define a validation method, set an event when validation method is triggered, set an error message (optional — error can be provided from server), and set the field where the message is shown (optional — by default is the given input field).

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Ideally, users fill in the form with necessary information and finish the job successfully. These requirements turned into the main characteristics of this solution: element (type=email, number, …), we also have constraint validation (required, maxlength, …) to ease the work of checking the form content on the client side.

Constraint validation is an algorithm browsers run natively when a form is submitted to determine its validity.

On this approach, we took advantage of the constraint validation API to perform validations.

This allows us to know if a particular field is valid or invalid at a given time, and makes it possible to give the user feedback right away.

The validity property gets a validity State object with the information of which validations failed and which didn’t.

Here’s how it looks: Finally, we map these properties with the data attributes of the input field to obtain the error messages.We will explain that in detail in the next section.Each input field stores all possible error messages in data attributes.Lisa Wollin Microsoft Corporation May 2004 Applies to: Microsoft® Office Front Page® 2003 Microsoft Front Page 2002 Microsoft Front Page 2000 Summary: Learn how validate HTML form fields using Java Script in Microsoft Office Front Page 2003.This article assumes a general understanding of HTML and Java Script.Note Front Page Server Extensions are a set of programs that provide access to special Front Page features, such as database processing, form processing, hit counters, and other built-in Front Page components that require server-side processing.

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