Webforms & JavaScript

Webforms enable websites to collect information (input) that are user enters. inputs can be text, numbers, checkboxes, drop-downs etc.

Inputs can be added to a website database or be used in a search of a database.

Web forms can be created very easily in HTML, once actions are applied within the HTML code the form will work with basic functionality.

JavaScript is used to add behaviours to a webpage, such as formatting and change of colours. They can be used within web forms to make areas change colour as a user inputs invalid or no data for example, eg: Incorrect Password [box highlighted red].

Inactive Web Form (coded in HTML).



Active Web Form (coded in HTML, JavaScript).

JavaScript was most commonly found on the web in forms that included Captcha security etc. Although the new Captcha system most commonly used now uses HTML 5, something which is largely replacing JavaScript. 

When being ran, JavaScript is interpreted rather than being compiled. This is done because it needs to be translated into object code specific to the devices processor that it is running on. The interpreter does this line by line and then runs it. 

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