合并GridView的表头

合并GridView的表头：

<% @ Page Language="C#" AutoEventWireup="true"  CodeFile="Default.aspx.cs" Inherits="_Default"  %>

<! DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" >

< html  xmlns ="http://www.w3.org/1999/xhtml"   >
< head  runat ="server" >
     < title > Untitled Page </ title >
</ head >
< body >
     < form  id ="form1"  runat ="server" >
     < div >
         < asp:GridView  runat ="server"  ID ="GridView_Merge_Header"  BackColor ="LightGoldenrodYellow"  BorderColor ="Tan"  BorderWidth ="3px"  CellPadding ="2"  ForeColor ="Black"  GridLines ="None"  BorderStyle ="None"  CellSpacing ="2"  Font-Names ="Verdana"  Font-Size ="8pt"  OnRowCreated ="GridView_Merge_Header_RowCreated" >
             < FooterStyle  BackColor ="Tan"   />
             < SelectedRowStyle  BackColor ="DarkSlateBlue"  ForeColor ="GhostWhite"   />
             < PagerStyle  BackColor ="PaleGoldenrod"  ForeColor ="DarkSlateBlue"  HorizontalAlign ="Center"   />
             < HeaderStyle  BackColor ="Tan"  Font-Bold ="True"   />
             < AlternatingRowStyle  BackColor ="PaleGoldenrod"   />
         </ asp:GridView >
     </ div >
     </ form >
</ body >
</ html >

using  System;
using  System.Data;
using  System.Configuration;
using  System.Web;
using  System.Web.Security;
using  System.Web.UI;
using  System.Web.UI.WebControls;
using  System.Web.UI.WebControls.WebParts;
using  System.Web.UI.HtmlControls;

public   partial   class  _Default : System.Web.UI.Page 
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            GridView_Merge_Header.DataSource = GenerateDataSet();
            GridView_Merge_Header.DataBind();
        }
    }

    private DataSet GenerateDataSet()
    {
        DataSet ds= new DataSet("test");
        ds.ReadXml(HttpRuntime.AppDomainAppPath + "/Employee.xml");
        return ds;
    }
    protected void GridView_Merge_Header_RowCreated(object sender, GridViewRowEventArgs e)
    {
        if (e.Row.RowType == DataControlRowType.Header)
        {                    
            //Build custom header.
            GridView oGridView = (GridView)sender;
            GridViewRow oGridViewRow = new GridViewRow(0, 0, DataControlRowType.Header, DataControlRowState.Insert);
            TableCell oTableCell = new TableCell();

            //Add Department
            oTableCell.Text = "Department";
            oTableCell.ColumnSpan = 2;
            oGridViewRow.Cells.Add(oTableCell);

            //Add Employee
            oTableCell = new TableCell();
            oTableCell.Text = "Employee";
            oTableCell.ColumnSpan = 3;
            oGridViewRow.Cells.Add(oTableCell);

            oGridView.Controls[0].Controls.AddAt(0, oGridViewRow);
        }
    }
}

<? xml version="1.0" encoding="utf-8"  ?>
< EmployeeDetails >
   < Employee >
     < Department > Development </ Department >
     < DepartID > 2 </ DepartID >
     < Name > Rajendran </ Name >
     < Age > 25 </ Age >
     < Location > USA </ Location >
   </ Employee >
   < Employee >
     < Department > Development </ Department >
     < DepartID > 2 </ DepartID >
     < Name > Karthic </ Name >
     < Age > 25 </ Age >
     < Location > USA </ Location >
   </ Employee >
   < Employee >
     < Department > Testing </ Department >
     < DepartID > 2 </ DepartID >
     < Name > Karthikeyan </ Name >
     < Age > 25 </ Age >
     < Location > India </ Location >
   </ Employee >
   < Employee >
     < Department > Management </ Department >
     < DepartID > 4 </ DepartID >
     < Name > Vidhya </ Name >
     < Age > 24 </ Age >
     < Location > India </ Location >
   </ Employee >
   < Employee >
     < Department > School </ Department >
     < DepartID > -1 </ DepartID >
     < Name > Anandh </ Name >
     < Age > 24 </ Age >
     < Location > India </ Location >
   </ Employee >
   < Employee >
     < Department > Mechanic </ Department >
     < DepartID > 5 </ DepartID >
     < Name > Magesh </ Name >
     < Age > 25 </ Age >
     < Location > India </ Location >
   </ Employee >
   < Employee >
     < Department > Admin </ Department >
     < DepartID > 7 </ DepartID >
     < Name > Sabari </ Name >
     < Age > 25 </ Age >
     < Location > India </ Location >
   </ Employee >
   < Employee >
     < Department > Human Resource </ Department >
     < DepartID > 8 </ DepartID >
     < Name > Nirmal </ Name >
     < Age > 25 </ Age >
     < Location > India </ Location >
   </ Employee >
</ EmployeeDetails >