|
ondragenter Event |
Fires
on the target element when the user drags the object to a valid drop target.
dhtml语法
|
Inline HTML |
<ELEMENT ondragenter = "handler" ... > |
All platforms |
|
Event property |
object.ondragenter = handler |
JScript only |
|
object.ondragenter = GetRef("handler") |
Visual Basic Scripting Edition (VBScript) 5.0 or later |
|
|
Named script |
<SCRIPT |
Internet Explorer only |
Event Information
|
Bubbles |
Yes |
|
Cancels |
Yes |
|
To invoke |
· · |
|
Default action |
Calls the associated event handler. |
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.
Remarks
You
can handle the ondragenter event on the source or on the target
object. Of the target events, it is the first to fire during a drag operation.
Target events use the getData method to stipulate which data and data
formats to retrieve. The list of drag-and-drop target events includes:
· onpaste
· ondragenter
· ondrop
when
scripting custom functionality, use the returnvalue property to disable the default action.
DHTML代码范例
This
example shows when and where each event fires during a drag-and-drop operation
by listing each event and the name of the object firing it in a list box.
<HEAD>
<SCRIPT>
var oNewOption;
// Code for dynamically adding options to a
select.
function ShowResults()
{ //
Information about the events
// and what object fired them.
arg = event.type + " fired by
" + event.srcElement.id;
oNewOption = new Option();
oNewOption.text = arg;
oResults.add(oNewOption,0);
}
</SCRIPT>
</HEAD>
<BODY>
<P>Source events are wired up to this
text box.</P>
<INPUT ID=txtDragOrigin VALUE="Text
to Drag"
ondragstart="ShowResults()"
ondrag="ShowResults()"
ondragend="ShowResults()"
>
<P>Target events are bound to this text
box.</P>
<INPUT ID=txtDragDestination
VALUE="Drag Destination"
ondragenter="ShowResults()"
ondragover="ShowResults()"
ondragleave="ShowResults()"
ondrop="ShowResults()"
>
<SELECT ID=oResults SIZE=30>
<OPTION>List of Events Fired
</SELECT>
</BODY>