hai friends ,
i am using this code to get my requirement.it works perfectly.
but it was run serverside ,so little bit time taken & server performence down.
so please any one tel me how to write this code in javascript.

Protected Sub chkchild_CheckedChanged(ByVal sender As Object, ByVal e As System.EventArgs)
        HidCheckedNos1.Value = ""
        Dim ocheckedcount As Integer = 0

        Dim chk2 As CheckBox = DirectCast(GridView1.HeaderRow.FindControl("chkHeader"), CheckBox)

        For Each r As GridViewRow In GridView1.Rows
            Dim chkin As CheckBox = DirectCast(r.FindControl("chkchild"), CheckBox)
            If chkin.Checked = False Then
                chk2.Checked = False
                ocheckedcount += 1
            End If
            HidCheckedNos1.Value = ocheckedcount
        Next
        If HidCheckedNos1.Value = 0 Then
            chk2.Checked = True
        Else
            chk2.Checked = False
        End If
    End Sub