点击回车获得当点焦点所在控件的ID

点击回车取得当点焦点所在控件的ID

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"><HTML> <HEAD>  <TITLE> New Document </TITLE>  <META NAME="Generator" CONTENT="EditPlus">  <META NAME="Author" CONTENT="">  <META NAME="Keywords" CONTENT="">  <META NAME="Description" CONTENT="">  <script type="text/javascript">document.onkeydown = function(evt){var evt = window.event?window.event:evt;if(evt.keyCode==13) {alert(event.srcElement.id);}}</script> </HEAD> <BODY> 用户名： <input type="text" id="user" name="user" />密码：<input type="text" id="password" name="password"/><input type="button" id="submitButton" name="submitButton" value="提交" /> </BODY></HTML>

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