To use a keyboard shortcut, hold down one or more modifier keys while pressing the last key of the shortcut. For example, to use the shortcut Command-C (copy), hold down Command, press C, then release both keys. Mac menus and keyboards often use symbols for certain keys, including the modifier keys: 1  Command â.
The syntax of the JavaScript for â¦ in loop is as follows: 1  Iterates through all enumerable properties of an object. 2  Iterates through all used indices of array including all user-defined properties of array object, if any. 3  Thus it may be better to use a traditional for loop with a numeric index when iterating over arrays.
JavaScript contains a standard library 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 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.