Hi Sanjay
If this solution is useful for you then please vote.
In this code you have to write manually Checked Changed event.
Example-----
<asp:Templatefield headertext="Check" >
<itemtemplate>
<asp:checkbox id="Chk1" runat="server" autopostback="True"
oncheckedchanged="chk1_CheckedChanged" />
</itemtemplate>
In this code you have to write manually "oncheckedchanged="chk1_CheckedChanged" you have to change only your check box name here is check box name is "chk1"
Now the below is the code behind the event.
protected void chk1_CheckedChanged(object sender, EventArgs e)
{
GridViewRow selectedRow = (GridViewRow)((CheckBox)sender).NamingContainer;
int RowIndex = selectedRow.RowIndex;
Label lbl_A = (Label)GridView1.Rows[RowIndex].FindControl("lbl_A");
}
In this back end code you can find control and perform any operation on the check box checked event.
If you have any doubt please ask.