GridView相同内容合并单元格

using System;
using System.Data;
using System.Configuration;
using System.Collections;
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 main : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {   // bind();
        Gridview_RowSpan(GridView1);

}

public static void Gridview_RowSpan(System.Web.UI.WebControls.GridView gv)
    {
        //合并单元格
        for (int i = 0; i < gv.Rows.Count - 1; i++)
        {
            int colnum = 1;
            int j;
            for (j = i + 1; j < gv.Rows.Count; j++)
            {
                if (gv.Rows[i].Cells[0].Text == gv.Rows[j].Cells[0].Text)
                {
                    colnum++;
                    gv.Rows[i].Cells[0].RowSpan = colnum;
                    gv.Rows[j].Cells[0].Visible = false;
                    gv.Rows[i].Cells[1].RowSpan = colnum;
                    gv.Rows[j].Cells[1].Visible = false;
                    gv.Rows[i].Cells[2].RowSpan = colnum;
                    gv.Rows[j].Cells[2].Visible = false;
                    gv.Rows[i].Cells[3].RowSpan = colnum;
                    gv.Rows[j].Cells[3].Visible = false;
                    gv.Rows[i].Cells[4].RowSpan = colnum;
                    gv.Rows[j].Cells[4].Visible = false;
                    gv.Rows[i].Cells[5].RowSpan = colnum;
                    gv.Rows[j].Cells[5].Visible = false;
                    gv.Rows[i].Cells[6].RowSpan = colnum;
                    gv.Rows[j].Cells[6].Visible = false;
                    gv.Rows[i].Cells[7].RowSpan = colnum;
                    gv.Rows[j].Cells[7].Visible = false;
                    gv.Rows[i].Cells[8].RowSpan = colnum;
                    gv.Rows[j].Cells[8].Visible = false;
                }
                else
                    break;
            }
            i = j - 1;
        }
    }

}