C# - How To Get Sorting Without Removing Row-Created Function(Use For Changing Column Of Header-text In Run-time)

The following code is my Grid View AA from aspx page.

<asp:GridView ID="GridView_AA" runat="server" OnSorting = "Gridview_AA_Sorting" OnRowCreated="GridView_AA_RowCreated">
<asp:TemplateField HeaderText="Period Name" SortExpression="PERIOD_NAME">
[code]...

I cannot sort after adding GridView_AA_RowCreated function. Each column of Grid view header-text worked well before I add this Row Created function. If I cut the following code: e.Row.Cells[2].Text = "Period Name";
Sorting works. I want to get sorting without removing this Row Created function. Do you have any brighter solution about my problem?

protected void GridView_AA_RowCreated(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.Header)
{
e.Row.Cells[2].Text = "Period Name"; //Change header text in run-time
}
}