问题是

</p> <input ondragover="this.value='';" ondragdrop="this.value='';" onmouseup="this.value='';"value="12345" /> <p> [Ctrl+A 全部选择 提示：你可先修改部分代码，再按运行]

这是 DOM 参考

http://www.mozilla.org/docs/dom/domref/dom_event_ref33.html#1000062

下面是我在 MozillaZine Forums 提问的答复

以下为引用内容:

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You’ll probably need to attach the events to the object using script rather than putting attributes in the tag. The attributes are not valid (X)HTML

Have a look at addEventListner, to see how to add events. Be warned that you are stepping into a minefield of browser incompatiblity.

See the spec for the input elment in HTML 4

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以下为引用内容:

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It may depend on what you’re trying to drag. If I get time I may tinker wtih this today. “addEventListener” may be the method you want to use, but it will have to be coupled with IE’s version of that method.

document.forms[0].elements[0].ondragover = function() { this.value = ”; } // may work, too.

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guoshuang2005-03-01+几天有时间看到这个，试验了一下，不是这些问题，继续期待答案

</p> <form> <input id="aaa" ondragover="this.value='';" value="12345" /> 111111111111111</form> <p><script></p> <p>//document.getElementById("aaa").ondragover=function(){alert(1)}</p> <p>//document.forms[0].elements[0].ondragover = function() {alert(1)} </p> <p>//document.forms[0].elements[0].addEventListener(”dragenter”,function(){alert(1)},false)</p> <p></script></p> <p> [Ctrl+A 全部选择 提示：你可先修改部分代码，再按运行]