高手指点一下啊 ，弄了好长时间没搞好

<asp:RadioButton   ID= "rdoGZ "   runat= "server "   GroupName= "rdoCity "   Text= "广州 "   Checked= "True "   OnCheckedChanged= "rdoGZ_CheckedChanged "   />
                &nbsp; <asp:RadioButton   ID= "rdoSZ "   runat= "server "   GroupName= "rdoCity "   Text= "深圳 "   OnCheckedChanged= "rdoSZ_CheckedChanged "   />
                <asp:DropDownList   ID= "ddltSanjak "   runat= "server ">


为什么如上的radiobutton不能触发如下的事件：

        protected   void   rdoSZ_CheckedChanged(object   sender,   EventArgs   e)
        {
                InitddltSanjak();
        }
        protected   void   rdoGZ_CheckedChanged(object   sender,   EventArgs   e)
        {
                Response.Write( "ggg ");
        }

------解决方案--------------------
将rdoGZ的AutoPostBack属性设为True。