GridView实现用"..."代替超长字符串

后台全部代码：
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;
using System.Data.SqlClient;

public partial class _Default : System.Web.UI.Page
{

//QQ:272912705 光之翼 www.hi.baidu.com/jcomet
    SqlConnection sqlcon;
    SqlCommand sqlcom;
    string strCon = "Data Source=(local);Database=北风贸易;Uid=sa;Pwd=sa";
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            ViewState["SortOrder"] = "身份证号码";
            ViewState["OrderDire"] = "ASC";
            bind();
        }
    }
    protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
    {
        GridView1.EditIndex = e.NewEditIndex;
        bind();
    }
    protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)
    {
        string sqlstr = "delete from 飞狐工作室 where 身份证号码='" + GridView1.DataKeys[e.RowIndex].Value.ToString() + "'";
        sqlcon = new SqlConnection(strCon);
        sqlcom = new SqlCommand(sqlstr,sqlcon);
        sqlcon.Open();
        sqlcom.ExecuteNonQuery();
        sqlcon.Close();
        bind();
    }
    protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
    {
        sqlcon = new SqlConnection(strCon);
        string sqlstr = "update 飞狐工作室 set 姓名='"
            + ((TextBox)(GridView1.Rows[e.RowIndex].Cells[1].Controls[0])).Text.ToString().Trim() + "',家庭住址='"
            + ((TextBox)(GridView1.Rows[e.RowIndex].Cells[3].Controls[0])).Text.ToString().Trim() + "' where 身份证号码='"
            + GridView1.DataKeys[e.RowIndex].Value.ToString() + "'";
        sqlcom=new SqlCommand(sqlstr,sqlcon);
        sqlcon.Open();
        sqlcom.ExecuteNonQuery();
        sqlcon.Close();
        GridView1.EditIndex = -1;
        bind();
    }
    protected void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
    {
        GridView1.EditIndex = -1;
        bind();
    }
    public void bind()
    {
        string sqlstr = "select top 5 * from 飞狐工作室";
        sqlcon = new SqlConnection(strCon);
        SqlDataAdapter myda = new SqlDataAdapter(sqlstr, sqlcon);
        DataSet myds = new DataSet();
        sqlcon.Open();
        myda.Fill(myds, "飞狐工作室");
        GridView1.DataSource = myds;
        GridView1.DataKeyNames = new string[] { "身份证号码" };
        GridView1.DataBind();
        for (int i = 0; i <= GridView1.Rows.Count - 1; i++)
        {
            DataRowView mydrv;
            string gIntro;
            if (GridView1.PageIndex == 0)
            {
                mydrv = myds.Tables["飞狐工作室"].DefaultView[i];
                gIntro = Convert.ToString(mydrv["家庭住址"]);
                GridView1.Rows[i].Cells[3].Text = SubStr(gIntro, 2);
            }
            else
            {
                mydrv = myds.Tables["飞狐工作室"].DefaultView[i + (5 * GridView1.PageIndex)];
                gIntro = Convert.ToString(mydrv["家庭住址"]);
                GridView1.Rows[i].Cells[3].Text = SubStr(gIntro, 2);
            }
        }
      
        sqlcon.Close();
    }
    public string SubStr(string sString, int nLeng)
    {
        if (sString.Length <= nLeng)
        {
            return sString;
        }
        string sNewStr = sString.Substring(0, nLeng);
        sNewStr = sNewStr + "...";
        return sNewStr;
    }
    protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        //如果是绑定数据行
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
            ////鼠标经过时，行背景色变
            //e.Row.Attributes.Add("onmouseover", "this.style.backgroundColor='#E6F5FA'");
            ////鼠标移出时，行背景色变
            //e.Row.Attributes.Add("onmouseout", "this.style.backgroundColor='#FFFFFF'");

            ////当有编辑列时，避免出错，要加的RowState判断
            //if (e.Row.RowState == DataControlRowState.Normal || e.Row.RowState == DataControlRowState.Alternate)
            //{
            //    ((LinkButton)e.Row.Cells[6].Controls[0]).Attributes.Add("onclick", "javascript:return confirm('你确认要删除：\"" + e.Row.Cells[1].Text + "\"吗?')");
            //}

        }
        if (e.Row.RowIndex != -1)
        {
            int id = e.Row.RowIndex + 1;
            e.Row.Cells[0].Text = id.ToString();
        }

    }
}