Chapter 15. O

Table of Contents
Obfuscation Needless complexity in the arrangement of tokens in a line of executable script.
Object There is a distinct difference between an object and an Object.
Object A native built-in type.
Object constant Constant objects.
Object inspector A debugging tool for inspecting object properties and classes.
Object literal An object initialiser that creates the object as well.
Object model There are several different object models that are realized in JavaScript implementations.
Object object An object of the class "Object".
Object() An Object object constructor.
Object() An Object object constructor.
Object.__parent__ A special property in which to access the scope chain during function execution.
Object.__proto__ A special property in which to access the prototype inheritance chain during construction.
Object.assign() A deprecated mechanism for intercepting messages sent to objects.
Object.Class Internal property that returns an object class.
Object.constructor A reference to a constructor object.
Object.eval() Evaluate the JavaScript source text passed in a string argument.
Object.hasOwnProperty() A method that can be used to test whether a property exists and belongs to the receiving object.
Object.isPrototypeOf() A test for the relationship between two objects to ascertain direct parentage.
Object.name This corresponds to the NAME attribute of the tag that creates the object.
Object.propertyIsEnumerable() A test for whether a property has the don't enumerate flag set or not.
Object.prototype The prototype for the Object object, which can be used to extend the interface for all Object objects.
Object.toLocaleString() Returns a string primitive version of the object taking the present locale into account during the translation.
Object.toSource() Output a string describing the object contents.
Object.toString() Return a string primitive version of an object.
Object.unwatch() A method to disable a watch that was set up on a property change.
Object.valueOf() The primitive numeric value of the object.
Object.watch() A means of establishing a call back when a property value changes.
Object property delimiter (.) A token to delimit object properties from their object.
OBJECT object This is an object that encapsulates an ActiveX plugin. Do not confuse it with the Object object that is the super-class of all objects in JavaScript.
OBJECT.align An alignment control for an <OBJECT> tag's position with respect to its parent object.
OBJECT.altHtml A block of alternative HTML to be used if the <OBJECT> tag fails to load its plugin correctly.
OBJECT.archive A space-separated archive list. This enumerates a set of classes that must be pre-loaded before the object can execute.
OBJECT.border The width of the border around the object when it is rendered into the display.
OBJECT.classid The URL that locates the registered ActiveX control within the local file system when MSIE is used on the Windows platform.
OBJECT.code The name of a Java applet to be used with the <OBJECT> tag.
OBJECT.codeBase The path to the directory where the Java applet denoted by the CLASS="..." HTML tag attribute is to be found.
OBJECT.codeType A description of the type of code in the object referred to by the CLASSID="..." HTML tag attribute.
OBJECT.data A URL that points at a file containing data that the OBJECT element can access.
OBJECT.declare A means of defining the object without activating it.
OBJECT.form The form that an object belongs to if it is used for form input.
OBJECT.height The height of an area reserved for displaying the contents of the <OBJECT> tag.
OBJECT.hspace A horizontal margin space either side of the <OBJECT> tag with respect to its surrounding objects.
OBJECT.name The value of the NAME="..." HTML tag attribute.
OBJECT.object An accessor that yields a reference to the containing JavaScript object when there is a possibility of naming conflicts between internally visible and externally visible property names.
OBJECT.readyState The current status disposition of the <OBJECT> tag as it is being loaded.
OBJECT.standby Sets or resets the message text displayed while the object is loading.
OBJECT.tabIndex A control of where the OBJECT object appears in the tabbing order of the page.
OBJECT.type An indication of the MIME type of the object if its codeType property is undefined.
OBJECT.useMap The URL of a <MAP> defined hash element that defines a client-side image map.
OBJECT.vspace A vertical spacing above and below the <OBJECT> with respect to its adjacent objects.
OBJECT.width The height of an area reserved for displaying the contents of the <OBJECT> tag.
Obsolescent A feature of the language that is no longer supported.
Octal value A numeric value based on a radix of 8.
Off by one errors An error caused by missing the target value by one.
Off-screen image caching A technique for caching images locally in readiness for an animation.
offscreenBuffering An alias for the window.offScreenBuffering property.
OL object An object that represents the ordered list contained in an <OL> tag.
OL.compact A switching attribute that condenses the space required to display the ordered list on the screen.
OL.start The starting index of items in the ordered list. The enumerator can be set to a predetermined value with this property.
OL.type The presentation style of the ordered list.
on ... All event handlers begin with the word on.
onAbort An event that happens when loading is interrupted.
onAfterPrint Called when printing is completed.
onAfterUpdate An event that happens after an update.
onBack Triggered by the back button.
onBeforeCopy Called immediately before a copy operation.
onBeforeCut Called immediately before a cut operation.
onBeforeEditFocus Called immediately before focus is relocated to another object.
onBeforePaste Called immediately before a paste operation.
onBeforePrint Called immediately before printing commences.
onBeforeUnload An event called before an unload happens.
onBeforeUpdate An event called before an update happens.
onBlur Triggered when the user selects another form element for input and the current one loses focus.
onBounce Triggered when a marquee element hits the edge of its element area.
onChange Triggered when the value belonging to an input element is changed.
onClick This event is triggered when the user clicks the mouse button with the pointer over the Element object that represents the object on screen.
onContentReady A special event handler provided to facilitate the loading of behavior controls.
onContextMenu Called when a context menu is requested by the user.
onCopy Called when a copy operation is requested by the user.
onCut Called when a Cut operation is requested by the user.
onDataAvailable Some data has arrived asynchronously from an applet or data source.
onDataSetChanged A data source has changed the content or some initial data is now ready for collection.
onDataSetComplete There is no more data to be transmitted from the data source.
onDblClick Triggered when the user double-clicks on an object.
onDocumentReady A special event to signify that a document is loaded and ready for use.
onDrag Called when a Drag is activated by the user.
onDragDrop Some data has been dropped onto a window.
onDragEnd Called when the drag finishes and the dragged object is dropped and released.
onDragEnter Called when a dragged object enters the receiving object.
onDragLeave Called when a dragged object leaves the receiving object.
onDragOver Called repeatedly while the dragged object is over the receiving object.
onDragStart The user has commenced some data selection with a mouse drag.
onDrop Called when a dragged object is dropped into a receiving window.
onError Triggered if an error occurs when loading an image.
onErrorUpdate An error has occurred in the transfer of some data from a data source.
onFilterChange A filter has changed the state of an element or a transition has just been completed.
onFinish Triggered when a marquee object has finished looping.
onFocus When the form element is selected for entry.
onForward When the forward button is clicked.
onHelp The user has pressed the [F1] key or selected [help] from the toolbar or menu.
onKeyDown Triggered when a key is pressed.
onKeyPress Pressing the key down and releasing it again triggers this event.
onKeyUp Triggered when a key is released.
onLoad Triggered when an object has completed loading.
onLoseCapture Called when capturing is deactivated for an object.
onMouseDown Triggered when the mouse button is pressed.
onMouseDrag An event handler for mouse drag operations.
onMouseMove Triggered when the mouse pointer is moved.
onMouseOut Triggered when the mouse pointer leaves the active area occupied by the Element object that represents the object on screen.
onMouseOver Triggered when the mouse pointer enters the active area owned by the object.
onMouseUp Triggered when the mouse button is released.
onMove The browser window has been moved.
onPaste Called when a Paste operation is requested by the user.
onPropertyChange Called when a property belonging to the receiving object is changed.
onReadyStateChange An object in the window has changed its ready state.
onReset The user has clicked a reset button in a form.
onResize As the window is resized, this event is triggered.
onRowEnter The data in a field bound to a data source is about to be changed.
onRowExit The data in a field bound to a data source has been changed.
onRowsDelete Some rows are about to be deleted from the database.
onRowsInserted Some new data is being inserted into the database.
onScroll The window has been scrolled.
onSelect Some textual content in the window has been selected.
onSelectStart A select action is beginning.
onStart Fires when a MARQUEE element is beginning its loop.
onStop Called when the user stops a page loading.
onSubmit The user has clicked on the submit button in a form.
onUnload Triggered when the document is unloaded.
open() An alias for the window.open() method.
opener An alias for the window.opener property.
OpenTV An interactive TV set-top box environment.
Opera A web browser alternative to MSIE and Netscape.
Operator A special symbolic token that when placed adjacent to or between values creates an expression.
Operator Precedence A means of controlling execution priority in expressions.
OptGroupElement object A means of grouping options together into logical sets.
OptGroupElement.disabled A switch for activating or deactivating a grouped option set.
OptGroupElement.label A label that is applied to a group of options.
Option object One of a set of objects belonging to a select object in a form.
Option() An Option object constructor.
Option.defaultSelected The selected state of this item when the form was created.
Option.index The index position within the select object set.
Option.label The text string that the user sees in the popup menu. This is another name for the Option.text property.
Option.prototype The prototype for the Option object that can be used to extend the interface for all Option objects.
Option.selected The selected state of this option item.
Option.text The text string that the user sees in the popup menu.
Option.value The text value that is returned to the server if this item is selected.
OptionElement object One of a set of objects belonging to a select object in a form.
OptionsArray object A collection object that belongs to a select popup.
OptionsArray.add() Adds a new option item to a select popup object.
OptionsArray.item() Access to a particular item in the options collection of a select popup object.
OptionsArray.length The number of options in a select popup.
OptionsArray.remove() Removes an option from the collection belonging to a select popup object.
OptionsArray.select() Select an item in an options array belonging to a select popup object.
outerHeight An alias for the window.outerHeight property.
outerWidth An alias for the window.outerWidth property.
Overview JavaScript language and functionality overview.