Validating html code
Also each browser has a slightly different default behaviour.
The simplest change you can make to your forms is to mark a text input field as 'required': This informs the (HTML5-aware) web browser that the field is to be considered mandatory.
In this article we intend to present only a number of simple examples to get you started, covering the basic form elements.
Before you ask, and someone always does, these examples will currently work in the following browsers: Safari 5, Chrome 6, Opera 9, Firefox 4 Beta and the i Phone/i Pad.
So if an older browser doesn't support them, the fact that they're in the HTML won't 'break' anything, they’ll just be rendered as an .
NB While client-side form validation is great for enhancing user experience—fast, instant feedback to the user without making a round trip to the server—you will still need to validate any data submitted on the server, too.
For these examples we have created our own valid/invalid CSS formatting to override the browser default. That's why you may see something like the following: Before you type anything into the box a red marker is shown.
by Christopher Heng, Whether you design your web page using a visual web editor like Expression Web, Dreamweaver or Blue Griffon, or you code HTML directly with a simple text editor, the generally recommended practice is to validate it after you finish designing it.
If your site has hundreds of pages, it is likely generated by a CMS such as Wordpress, Drupal or such.
An HTML validator is a quality assurance program used to check Hypertext Markup Language ( HTML ) markup elements for syntax errors.
A validator can be a useful tool for an HTML user who receives data electronically from a variety of input sources.
This article discusses what validation means, points you to some of the free tools that you can use, and deals with its limitations and the problems that a new webmaster may face. Otherwise you'll be completely lost here since I assume you at least know what these terms mean.
Note: if you are not sure what HTML and CSS mean, please read What are HTML, CSS, Java Script, PHP and Perl? For those unfamiliar with the term, "validating" a page is just a jargon-filled way of referring to the use of a computer program to check that a web page is free of errors.
I know W3C has a site you can go to that will validate an HTML page (and count how many errors are found for a given doctype), but that has to be a publicly available URL.