各位大神帮看看，为什么总是指定的参数已超出有效值的范围。

代码如下：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.OleDb;
using System.Configuration;public partial class Main : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        using (OleDbConnection olecon = new OleDbConnection(ConfigurationManager.ConnectionStrings["conn"].ToString()))
        {
            string name = Session["name"].ToString();            {
                try
                {
                    olecon.Open();
                    OleDbCommand oledbcommand = new OleDbCommand("select * from StudentInfo where StudentId='" + name + "'", olecon);
                    OleDbDataReader da = oledbcommand.ExecuteReader();
                    this.GridView1.DataSource = da;
                    this.GridView1.DataKeyNames = new string[] { "StudentId" };
                    this.GridView1.DataBind();
                    da.Close();
                }
                catch (Exception)
                {
                    throw;
                }
            }
        }
    }
    protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
    {
        GridView1.EditIndex = e.NewEditIndex;
    }
    protected void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
    {
        GridView1.EditIndex = -1;
    }
    protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
    {
        string A = GridView1.DataKeys[e.RowIndex].Value.ToString();
        string B = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[1].Controls[0])).Text.ToString().Trim();
        string C = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[2].Controls[0])).Text.ToString().Trim();
        string D = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[3].Controls[0])).Text.ToString().Trim();
        string E = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[4].Controls[0])).Text.ToString().Trim();
        string F = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[5].Controls[0])).Text.ToString().Trim();
        string G = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[6].Controls[0])).Text.ToString().Trim();
        string H = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[7].Controls[0])).Text.ToString().Trim();        string s = "update  StudentId='" + A + "',StudentName='" + B + "',Sex='" + C + "',DateOfBirth='" + D + "',Specialty='" + E + "',Email='" + F + "',Root='" + G + ",PassWord='" + H + "'";
        Response.Write("<script language=javascript> alert('数据更新成功！');window.location='ManagerNews.aspx'</script>");
     }
}GridView