public DataTable DDT=new DataTable (); //g公共变量
    protected void Page_Load(object sender, EventArgs e)
    {
               
        dt.Columns.Add(new DataColumn("a", typeof(string)));
        dt.Columns.Add(new DataColumn("b", typeof(string)));
        dt.Columns.Add(new DataColumn("c", typeof(string)));

    }
 
    protected void Button2_Click(object sender, EventArgs e)
    {
        //this.grid.DataSource = null;
        //this.grid.DataBind();
        DataRow MMW = DDT.NewRow();
        MMW["a"] = "aa";
          MMW["b"] = "bb";
          MMW["c"] = "cc";
          DDT.Rows.Add(MMW);
          this.grid.DataSource = DDT;
          this.grid.DataBind();


    }