Javascript Course Notes
JavaScript Essentials
The purpose of most JavaScript scripts is to make a Web page interactive, whether or not a program is running on the server to enhance that interactivity. Making a page interactive means tracking user action and responding with some visible change on the page. The avenues for communication between user and script include familiar onscreen elements, such as fields and buttons, as well as dynamic.
To assist the scripter in working with these elements, the browser and JavaScript implements them as software objects. These objects have properties that often define the visual appearance of the object. Objects also have methods, which are the actions or commands that an object can carry out.
Finally, these objects have event handlers that trigger the scripts you write in response to an action in the document (usually instigated by the user).
JavaScript is a cross-platform, object-oriented scripting language. JavaScript is a small, lightweight language; it is not useful as a standalone language, but is designed for easy embedding in other products and applications, such as web browsers. Inside a host environment, JavaScript can be connected to the objects of its environment to provide programmatic control over them.
Core JavaScript contains a core set of objects, such as Array, Date, and Math, and a core set of language elements such as operators, control structures, and statements. Core JavaScript can be extended for a variety of purposes by supplementing it with additional objects; for example: * Client-side JavaScript extends the core language by supplying objects to control a browser (Navigator or another web browser) and its Document Object Model (DOM). For example, client-side extensions allow an application to place elements on an HTML form and respond to user events such as mouse clicks, form input, and page navigation. * Server-side JavaScript extends the core language by supplying objects relevant to running JavaScript on
The purpose of most JavaScript scripts is to make a Web page interactive, whether or not a program is running on the server to enhance that interactivity. Making a page interactive means tracking user action and responding with some visible change on the page. The avenues for communication between user and script include familiar onscreen elements, such as fields and buttons, as well as dynamic.
To assist the scripter in working with these elements, the browser and JavaScript implements them as software objects. These objects have properties that often define the visual appearance of the object. Objects also have methods, which are the actions or commands that an object can carry out.
Finally, these objects have event handlers that trigger the scripts you write in response to an action in the document (usually instigated by the user).
JavaScript is a cross-platform, object-oriented scripting language. JavaScript is a small, lightweight language; it is not useful as a standalone language, but is designed for easy embedding in other products and applications, such as web browsers. Inside a host environment, JavaScript can be connected to the objects of its environment to provide programmatic control over them.
Core JavaScript contains a core set of objects, such as Array, Date, and Math, and a core set of language elements such as operators, control structures, and statements. Core JavaScript can be extended for a variety of purposes by supplementing it with additional objects; for example: * Client-side JavaScript extends the core language by supplying objects to control a browser (Navigator or another web browser) and its Document Object Model (DOM). For example, client-side extensions allow an application to place elements on an HTML form and respond to user events such as mouse clicks, form input, and page navigation. * Server-side JavaScript extends the core language by supplying objects relevant to running JavaScript on