function doadd()
{
if (document.flow_setting.mnop.options.length=="0")
{
alert('wrong!!!');
}
else
{
document.flow_setting.submit();
}
}
{
if (document.flow_setting.mnop.options.length=="0")
{
alert('wrong!!!');
}
else
{
document.flow_setting.submit();
}
}
<script>
function doadd()
{
if (document.flow_setting.mnop.options.length=="0")
{
alert('wrong!!!');
}
else
{ alert(document.flow_setting.add.value)//可以
document.flow_setting.submit();
}
}
</script>
<form action=1.asp method=post name=flow_setting>
<select name=mnop>
<option>d
</select>
<input type=button class=w3dButton name="add" value="Add" onClick="doadd()">
</form>