find checkbox control in datagrid?

hi!
i am display checkboxes in my datagrid. (user select the checkbox and click delete button that record has deleted)
i am write code for testing like
dim cb as checkbox = directcast(datagrid1.FindControl("chkSelect"),CheckBox)
cb = new checkbox()
if cb.checked = true then
msgbox("Checked")
Else
msgbox("un Checked")
End if
my problem is when i checked the checkbox it display Un checked in msgbox. please correct my code. and give any example of giving this type of checkboxes and delete buttons in datagrid.
Thanks