FindControl

//一般 FindControl RadioButton為例
((RadioButton)grid_view.Rows[i].FindControl("RadioButton2")).Checked == false




 foreach (GridViewRow item in grid_view.Rows)
{

    if (((RadioButton)item.FindControl("RadioButton2")).Checked == true)
            {
             ....
            }

}


///指定當下選擇的物件

 protected void RadioButton_CheckedChanged(object sender, EventArgs e)
 {


            string RadioNowGUAR_SYSID = ((Label)((RadioButton)sender).NamingContainer.FindControl("lblGUAR_SYSID")).Text;
....
}