asp.net服务器控件调用js

<asp:DropDownList id="DropDownList1" runat="server">
<asp:ListItem Value="1">11111</asp:ListItem>
<asp:ListItem Value="2">222222</asp:ListItem>
</asp:DropDownList>
<div id="div1">11111</div>
<div id="div2">22222</div>

function change()
}