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ondragstart Event


Fires on the source object when the user starts to drag a text selection or selected object.

Syntax

Inline HTML<ELEMENT ondragstart = "handler" ... >All platforms
Event propertyobject.ondragstart = handlerJScript (compatible with ECMA 262 language specification) only
Named script<SCRIPT FOR = object EVENT = ondragstart>Internet Explorer only

Remarks

BubblesYes
CancelsYes
To invoke Drag the selected text or object.
Default action Calls the associated event handler.

The ondragstart event is the first to fire when the user starts to drag the mouse. It is essential to every drag operation, yet is just one of several source events in the data transfer object model. Source events use the setData method of the dataTransfer object to provide information about data being transferred. Source events include ondragstart, ondrag, and ondragend.

Event Object Properties

Although event handlers in the DHTML Object Model do not receive parameters directly, the handler can query the event object for data.

Event Object Properties

altKeyRetrieves the current state of the ALT key.
cancelBubbleSets or retrieves whether the current event should bubble up the hierarchy of event handlers.
clientXRetrieves the x-coordinate of the mouse cursor relative to the client area of the window, excluding window decorations or scroll bars.
clientYRetrieves the y-coordinate of the mouse cursor relative to the client area of the window, excluding window decorations or scroll bars.
ctrlKeyRetrieves the state of the CTRL key.
dataTransferProvides access to predefined clipboard formats for use in drag-and-drop operations.
offsetXRetrieves the horizontal coordinate of the mouse's position relative to the object firing the event.
offsetYRetrieves the vertical coordinate of the mouse's position relative to the object firing the event.
returnValueSets or retrieves the return value from the event.
screenXRetrieves the horizontal position of the mouse, in pixels, relative to the user's screen.
screenYRetrieves the vertical position of the mouse, in pixels, relative to the user's screen.
srcElementRetrieves the object that fired the event.
typeRetrieves the event name from the event object.
xRetrieves the x-coordinate of the mouse cursor relative to the parent element.
yRetrieves the y-coordinate of the mouse cursor relative to the parent element.

Example

The first example shows how to detect the tagName property of the object from which the ondragstart event has originated. The second example shows how to order event firing for drag-and-drop events.

Sample Code

This example uses event bubbling to handle the ondragstart event at the BODY level.

<BODY ondragstart="alert(event.srcElement.tagName)">
  <INPUT TYPE=text VALUE="Select and drag this text">
  <SPAN>Select and drag this text</SPAN>
  <TEXTAREA>Select and drag this text</TEXTAREA>
</BODY>

This feature requires Internet Explorer 5 or later. Click the icon below to install the latest version. Then reload this page to view the sample.
Microsoft Internet Explorer

This example shows how to control when each event fires during a drag-and-drop operation.

<HEAD>
<SCRIPT>
function ShowResults(){
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>

This feature requires Internet Explorer 5 or later. Click the icon below to install the latest version. Then reload this page to view the sample.
Microsoft Internet Explorer

Applies To

[ Object Name ]
PlatformVersion
Win16:
Win32:
Mac:
Unix:
WinCE:
A, ACRONYM, ADDRESS, AREA, B, BDO, BIG, BLOCKQUOTE, BODY, CAPTION, CENTER, CITE, CODE, custom, DD, DEL, DFN, DIR, DIV, DL, document, DT, EM, FIELDSET, FONT, FORM, Hn, HR, I, IMG, INPUT type=button, INPUT type=checkbox, INPUT type=file, INPUT type=image, INPUT type=password, INPUT type=radio, INPUT type=reset, INPUT type=submit, INPUT type=text, KBD, LABEL, LI, LISTING, MAP, MARQUEE, MENU, NEXTID, NOBR, OBJECT, OL, P, PLAINTEXT, PRE, Q, RT, RUBY, S, SAMP, SMALL, SPAN, STRIKE, STRONG, SUB, SUP, TABLE, TBODY, TD, TEXTAREA, TFOOT, TH, THEAD, TR, TT, U, UL, VAR, XMP

See Also

DHTML Data Transfer Overview, ondrop



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