SqlConnection myconn=new SqlConnection("server=(local);database=zzrkpcs;uid=sa;pwd=");
SqlDataAdapter mydroupcmd=new SqlDataAdapter("select dmpcs_tab.dmmc from dmpcs_tab where dmzm like '330282%' order by substring(dmzm,1,6)",myconn);
DataSet mydroupdr=new DataSet();
mydroupcmd.Fill(mydroupdr,"dmpcs");
DropDownList1.DataSource=mydroupdr.Tables["dmpcs"];
DropDownList1.DataValueField="dmmc";
DropDownList1.DataTextField="dmmc";
DropDownList1.DataBind();
}