Problem in paging of gridview

protected void grdView_RowCommand(object sender, GridViewCommandEventArgs e)
    {
        int index = Convert.ToInt32(e.CommandArgument);
        try
        {
            GridViewRow row =grdView.Rows[index];
            Label lbl = (Label)row.Cells[0].FindControl("lblName");
            Name = lbl.Text;
            lblDocname.Text = Name;
        }
        catch (Exception ex)
        {
            Response.Write(ex);
        }
    }
protected void grdView_PageIndexChanging(object sender, GridViewPageEventArgs e)
    {
        grdView.PageIndex = e.NewPageIndex;
        bindgrid();
    }