错误：“HtmlSelect”不能有类型为“LiteralControl”的子级。
<select id="DDLYear" onchange="toDate()" style="width: 71px" runat="server">
<script>for(i=1970;i<=2010;i++)document.write("<option>"+i+"</option>")</script>
</select>
年
<select id="DDLMonth" onchange="toDate()" style="width: 78px" runat="server">
<script>for(i=1;i<=12;i++)document.write("<option>"+i+"</option>")</script>
</select>
月
<select id="DDLDay" onchange="toDay()" style="width: 71px" runat="server">
</select>
