How to get checkbox value in gridview

even if my checkbox checked insde gridview this condtion not satisfying means not enterin if loop.
what could be reason.Is it correct way to get checkbox id in gridview
public void name()
{
foreach (GridViewRow g in ((GridView)(Session["gview"])).Rows)
{
if (((CheckBox)g.FindControl("chkSelect")).Checked==true)
{
str1[i] = ((System.Web.UI.WebControls.Label)g.FindControl("lbl1")).Text;
str2[i] = ((System.Web.UI.WebControls.Label)g.FindControl("lbl2")).Text;
i++;
}
}
}