attachEvent

HTML (DHTML)

attachEvent Method

Internet Development Index

Binds the specified function to an event, so that the function gets called whenever the event fires on the object.

Syntax

bSuccess = object.attachEvent(sEvent, fpNotify)

Parameters

sEvent Required. String that specifies any of the standard DHTML Events.
fpNotify Required. Pointer that specifies the function to call when sEvent fires.

Return Value

Boolean. Returns one of the following possible values:

trueThe function was bound successfully to the event.
falseThe function was not bound to the event.

Remarks

When sEvent fires on the object, the object's sEvent handler is called before fpNotify , the specified function. If you attach multiple functions to the same event on the same object, the functions are called in random order, immediately after the object's event handler is called.

The attachEvent method enables a behavior to handle events that occur on the containing page. This method is not limited, however, to behaviors. You can also define a function on a page that attaches to events fired on the same page.

Behaviors that attach to events using the attachEvent method must explicitly call the detachEvent method to stop receiving notifications from the page when the ondetach event fires.

A behavior that attaches to events on the page using the HTML Component (HTC)?A HREF="/workshop/components/htc/reference/elements/attach.html">PUBLIC:ATTACH element automatically stops receiving notifications when the behavior detaches from the element, and does not need to call the detachEvent method.

Note  To use the attachEvent method with Microsoft® Visual Basic® Scripting Edition (VBScript), you need to use the GetRef to obtain a function pointer. The function pointer can then be passed to attachEvent.

Examples

This example shows how to implement a mouseover highlighting effect by calling the attachEvent method from an HTC.

<PUBLIC:ATTACH EVENT="ondetach" ONEVENT="cleanup()" />
<SCRIPT LANGUAGE="JScript">
attachEvent ('onmouseover', Hilite);
attachEvent ('onmouseout', Restore);
function cleanup()
{
detachEvent ('onmouseover', Hilite);
detachEvent ('onmouseout', Restore);
}
function Hilite()
{
if (event.srcElement == element)
{
normalColor = style.color;
runtimeStyle.color  = "red";
runtimeStyle.cursor = "hand";
}
}
function Restore()
{
if (event.srcElement == element)
{
runtimeStyle.color  = normalColor;
runtimeStyle.cursor = "";
}
}
</SCRIPT>
This feature requires Microsoft® Internet Explorer 5 or later. Click the following icon to install the latest version. Then reload this page to view the sample.

The following example shows how to use the attachEvent method with VBScript. When you click on the span's text, the event handler changes the background color.

<HTML>
<BODY ONLOAD="setupEventHandler()" LANGUAGE="VBS">
<SCRIPT LANGUAGE="VBS">
function setupEventHandler()
set fpchgBackground = getRef("chgBackground")
call mySpan.attachEvent("onclick", fpChgBackground)
end function
function chgBackground()
document.bgColor = "lemonchiffon"
end function
</SCRIPT>
<SPAN ID="mySpan">SPAN</SPAN>
</BODY>
</HTML>

Standards Information

There is no public standard that applies to this method.

Applies To

A, ACRONYM, ADDRESS, APPLET, AREA, B, BASE, BASEFONT, BGSOUND, BIG, BLOCKQUOTE, BODY, BR, BUTTON, CAPTION, CENTER, CITE, CODE, COL, COLGROUP, COMMENT, CUSTOM, DD, DEL, DFN, DIR, DIV, DL, document, DT, EM, EMBED, FIELDSET, FONT, FORM, FRAME, FRAMESET, HEAD, hn, HR, HTML, I, IFRAME, IMG, INPUT type=button, INPUT type=checkbox, INPUT type=file, INPUT type=hidden, INPUT type=image, INPUT type=password, INPUT type=radio, INPUT type=reset, INPUT type=submit, INPUT type=text, INS, KBD, LABEL, LEGEND, LI, LINK, LISTING, MAP, MARQUEE, MENU, namespace, NOBR, OBJECT, OL, OPTION, P, PLAINTEXT, PRE, Q, S, SAMP, SCRIPT, SELECT, SMALL, SPAN, STRIKE, STRONG, SUB, SUP, TABLE, TBODY, TD, TEXTAREA, TFOOT, TH, THEAD, TITLE, TR, TT, U, UL, VAR, window, XMP

See Also

detachEvent, Introduction to DHTML Behaviors, Using DHTML Behaviors, Using HTML Components to Implement DHTML Behaviors in Script