onbeforeactivate Event
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Fires immediately before the object is set as the active element.
dhtml语法
inline html <element onbeforeactivate = "handler" ... > All platforms Event property object.onbeforeactivate = handler JScript only object.onbeforeactivate = GetRef("handler") Visual Basic Scripting Edition (VBScript) 5.0 or later only Named script <SCRIPT FOR = object EVENT = onbeforeactivate> Internet Explorer only
Event Information
Bubbles Yes Cancels Yes To invoke
- Click on an element, other than the active element of the document.
- Use the keyboard to move focus from the active element to another element.
- Invoke the setactive method on an element, when the element is not the active element.
- invoke the focus method on an element, when the element is not the active element.
Default action Change activation from the event.fromelement to the event.srcelement.
Event Object Properties
Although event handlers in the DHTML Object Model do not receive parameters directly, a handler can query an event object for data.
altKey Sets or retrieves a value that indicates the state of the ALT key. altLeft Sets or retrieves a value that indicates the state of the left ALT key. wheelDelta Sets or retrieves the distance and direction the wheel button has rolled. ctrlKey Sets or retrieves the state of the CTRL key. ctrlLeft Sets or retrieves the state of the left CTRL key. shiftKey Sets or retrieves the state of the SHIFT key. cancelBubble Sets or retrieves whether the current event should bubble up the hierarchy of event handlers. clientX Sets or retrieves the x-coordinate of the mouse pointer's position relative to the client area of the window, excluding window decorations and scroll bars. clientY Sets or retrieves the y-coordinate of the mouse pointer's position relative to the client area of the window, excluding window decorations and scroll bars. offsetX Sets or retrieves the x-coordinate of the mouse pointer's position relative to the object firing the event. offsetY Sets or retrieves the y-coordinate of the mouse pointer's position relative to the object firing the event. screenX Retrieves the x-coordinate of the mouse pointer's position relative to the user's screen. screenY Sets or retrieves the y-coordinate of the mouse pointer's position relative to the user's screen. fromElement Sets or retrieves the object from which activation or the mouse pointer is exiting during the event. shiftLeft Retrieves the state of the left SHIFT key. srcElement Sets or retrieves the object that fired the event. type Sets or retrieves the event name from the event object. x Sets or retrieves the x-coordinate, in pixels, of the mouse pointer's position relative to a relatively positioned parent element. y Sets or retrieves the y-coordinate, in pixels, of the mouse pointer's position relative to a relatively positioned parent element.
Remarks
With Internet Explorer 5.5 and later, focus on a document, and the active element of a document can be managed separately. With Internet Explorer 6 and later, use the onbeforeactivate event to cancel setting an element as active. Canceling an element's onbeforeactivate event has three different behaviors, depending on the action which fired the event.
- When fired by a user clicking on the element, canceling will force the focus on the parent element and bubble up the chain until it hits a focusable element.
- when fired by a user tabbing through the document, canceling will force the focus on the next element in the taborder. shift-tab will force the focus on the previous element in the taborder.
- when fired programmatically by the focus or the document.setactive methods, canceling will have no effect.
Note The onbeforeactivate event cannot be canceled when fired programmatically.Each document may have up to one active element. Set the active element with the setactive or focus methods. using the setactive method has no effect on document focus. using the focus method on an individual element causes the element to gain focus and become the active element.
using the focus method on a document that does not have the focus moves the document to the front of the display. additionally, the document's active element gains focus.
for a given display, only one element has focus at any given time. striking a key directly affects only the element with focus. events fired by that keystroke may be scripted to affect other documents and child elements.
applies to
A, ADDRESS, APPLET, AREA, B, BDO, BIG, BLOCKQUOTE, BODY, BUTTON, CAPTION, CENTER, CITE, CODE, CUSTOM, DD, DFN, DIR, DIV, DL, document, DT, EM, EMBED, FIELDSET, FONT, FORM, hn, HR, I, IMG, INPUT type=button, INPUT type=checkbox, INPUT type=file, INPUT type=image, INPUT type=reset, INPUT type=password, INPUT type=radio, INPUT type=submit, INPUT type=text, KBD, LABEL, LEGEND, LI, LISTING, MAP, MARQUEE, MENU, nextID, NOBR, OL, P, PLAINTEXT, PRE, RT, RUBY, S, SAMP, SELECT, SMALL, SPAN, STRIKE, STRONG, SUB, SUP, TABLE, TBODY, TD, TEXTAREA, TFOOT, TH, THEAD, TR, TT, U, UL, VAR, XMP
更多语法参考
onactivate, onbeforedeactivate, ondeactivate, onfocusin, onfocusout