<script language="javascript">
<!--
function checkData(thisform){
if(thisform.hello.selectedIndex==-1){
alert("you must choose 1 choice at least");
}
}
//-->
</script>
<form name="frm01" id="frm01">
<select name="hello" mutiple size=3>
<option value=1>22</option>
<option value=1>24</option>
<option value=1>262</option>
</select>
<input type="button" value="check" onclick="checkData(document.frm01);">
</form>
加分啊
<!--
function checkData(thisform){
if(thisform.hello.selectedIndex==-1){
alert("you must choose 1 choice at least");
}
}
//-->
</script>
<form name="frm01" id="frm01">
<select name="hello" mutiple size=3>
<option value=1>22</option>
<option value=1>24</option>
<option value=1>262</option>
</select>
<input type="button" value="check" onclick="checkData(document.frm01);">
</form>
加分啊
解决方案 »
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