如何在多选下拉框中判断是单击还是双击？？

[pantech_36]

如题。
另外，能不详细讲一讲，单击和双击事件。以及如何应用到button中

[wsj]

ondblclick Event

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Fires when the user double-clicks the object.

Applies To

VAR
Platform Version
Win16: 4.0

Win32: 4.0

WinCE: 4.0

Unix: 4.0

Mac: 4.0

Version data is listed when the mouse hovers over a link, or the link has focus.
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=password, INPUT type=radio, INPUT type=reset, INPUT type=submit, INPUT type=text, KBD, LABEL, LEGEND, LI, LISTING, MAP, MARQUEE, MENU, NEXTID, NOBR, OBJECT, 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
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