JS判断页面中的radio是否选中

<script language="javascript">function clicked(){for(var i=0;i<document.mxh.radio.length;i++){if(document.mxh.radio[i].checked)alert(document.mxh.radio[i].value+":选了")elsealert(document.mxh.radio[i].value+":没选") }}</script><form name=mxh><input type=radio name=radio value=1>1<input type=radio name=radio value=2>2<input type=radio name=radio value=3>3<input type=radio name=radio value=4>4<input type=radio name=radio value=5>5<input type=button value="查询" onclick=clicked()></form>

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