CheckBox Checked state inside gridview

Question

I have a simple gridview

Answer 1

Try this:

Check Wheather you have put your code for binding data to GridView in

If (!IsPostBack)
{
     //Code for Binding Data to GridView 
} 

Answer 2

my fault.i haven't done the following

  if (!Page.IsPostBack)
            {

                Binddata();//Bind data to gridview
            }

previously Binddata() method was not inside

if (!Page.IsPostBack)

which was causing the issue