c# - How to apply a filter expression to a gridview? -

i have grid view , filter expression database. want apply filter expression grid data grid sort. column criteria match column of grid. isn't problem.

i can set grid.filterexpression = filter , how can sort values grid filter criteria?

code: html markup populate dropdowns

<asp:sqldatasource id="sqldatasourcecity" runat="server"  connectionstring="<%$ connectionstrings:northwindconnectionstring %>"  selectcommand="select distinct city customers"> </asp:sqldatasource>   <asp:dropdownlist id="ddlcountry" runat="server"                    appenddatabounditems="true"                    autopostback="true"                    datasourceid="sqldatasourcecountry"                    datatextfield="country"                    datavaluefield="country" width="100px"> <asp:listitem value="%">all</asp:listitem> </asp:dropdownlist>   <asp:sqldatasource id="sqldatasourcecountry" runat="server"  connectionstring="<%$ connectionstrings:northwindconnectionstring %>"  selectcommand="select distinct [country] [customers]"> 

html markup of gridview , sqldatasource filter expression

<asp:gridview id="gridview1" runat="server"                allowpaging="true"                datasourceid="sqldatasourcegridview"                autogeneratecolumns="false"               cssclass="gridviewstyle"                gridlines="none" width="650px"                showheader="false"> <columns> <asp:boundfield datafield="customerid" headertext="customer id"/> <asp:boundfield datafield="companyname" headertext="company"/> <asp:boundfield datafield="contactname" headertext="name"/> <asp:boundfield datafield="city" headertext="city"/> <asp:boundfield datafield="country" headertext="country"/> </columns> </asp:gridview>   <asp:sqldatasource id="sqldatasourcegridview"                     runat="server"  connectionstring="<%$ connectionstrings:northwindconnectionstring %>"  selectcommand="select [customerid], [companyname], [contactname],  [city], [country] [customers]"  filterexpression="[city] '{0}%' , [country] '{1}%'"> <filterparameters> <asp:controlparameter controlid="ddlcity" name="city"                        propertyname="selectedvalue"                        type="string" /> <asp:controlparameter controlid="ddlcountry" name="country"                        propertyname="selectedvalue"                        type="string" /> </filterparameters> </asp:sqldatasource> 

source :-http://csharpdotnetfreak.blogspot.com/2011/04/gridview-filterexpression-dropdownlist.html