how to bind single field of grid with multiple values using DataBinder.Eval

i have one hidden field and i want to bind it with two values of my data base separated by an coma. some thing like ->asp:HiddenField ID="hfRstidDate" runat="server" Value=<%# DataBinder.Eval(Container.DataItem, "tsk_ID"),DataBinder.Eval(Container.DataItem, "Date_Worked").ToString())%>

pleas开发者_高级运维 help

<asp:HiddenField runat="server" Value='<%#String.Concat(Eval("tsk_ID"),",",Eval("Date_Worked").ToString()) %>' />