Forms Data Controls :: How To Concate 2 Eval In Listview

i think its a simple problem but i am strugling with it i have list view, and in item template i am bounding a label with 2 fields that is first name and last name

i am tring this code

Text='<%# Eval("firstname") + Eval("lastname") %>'
/>

but it gives error taht Operator '+' cannot be applied to operands of type 'object' and 'object' for single value it works that is

Text='<%# Eval("firstname") %>'
/>
and even for constant concatenate it works that is
Text='<%# "India" + Eval("firstname") %>'
/> .... is working fine

I tried different arrangement but its not working that is

Text='<%# Eval("firstname","Lastname") %>'
/>
Text='<%# Eval("firstname" + "Lastname") %>'
/>