how do I we get to know which all the check box's are TICKED

Question

I have Datagrid in asp.net page with the below mentioned data 

Device Name	Column 1	Column 2
iPad	Check Box	Check Box
iPhone	Check Box	Check Box
iStore	Check Box	Check Box

 

Here Device_Name,Column1 and Column2 are column names, under these columns we have check boxes on both the columns, Please can anybody help me how do I we get to know which all the check box's are TICKED.

Once it has been TICKED I want to assign checked value (just to identify which are been ticked) to array list from Grid view (for storing purpose, later I will pass this array list to next page). 

This is my Code to generate dynamic check boxes in grid view

 protected void GrdOSInfo_RowDataBound(object sender, GridViewRowEventArgs e)

        {

         if (e.Row.RowType == DataControlRowType.DataRow)

            {

                for (int i = 1; i < 3; i++)

                {

                    //foreach (GridView row in GridView1.Rows)

                    //{

                    CheckBox chk = new CheckBox();

                    chk.EnableViewState = true;

                    chk.Enabled = true;

                    chk.ID = "chkb"+i;

                    

                    e.Row.Cells[i].Controls.Add(chk);

                    //}

                }

            }

        }

======================================

Could you please someone help me one this