You can use link button like following instead of hyperlink like following
<temTemplate>
<asp:LinkButton ID="finished" runat="server" CommandArgument='<%# EVAl("employeedetails") %>' OnClick="finished_Click" ><img src="pics/more.gif" alt="" style="border:0;" /></asp:LinkButton>
</ItemTemplate>
Here onclick I defined a function which You should define inside code behind like following.(see its VB code if need You can change it to C# by a converter )
Public Sub finished_Click(ByVal sender As Object, ByVal e As EventArgs)
//Code
End sub
If you are picking ID of that employee in '<%# EVAl("employeeID") %>' by using that ID You can fetch the detalis.
Please Mark Answer if You find Your solution