protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack) {
            
             DataClasses1DataContext _dc = new DataClasses1DataContext();
            var _data = _dc.zwgxx22(DateTime.Parse("2012-1-1"), DateTime.Parse("2012-8-23"));
            DataTable dt = new DataTable("dataset");
            dt.Columns.Add("MaxUpSpeed",typeof(int));  //列 务必带上数据类型 否则无法显示报表内容，并和rdlc上的数据源完全相同
            dt.Columns.Add("MaxDownSpeed", typeof(int));
            dt.Columns.Add("MinUpSpeed", typeof(int));
            dt.Columns.Add("MinDownSpeed", typeof(int));
            dt.Columns.Add("AvgUpSpeed", typeof(int));
            dt.Columns.Add("Datetime", typeof(DateTime));
            dt.Columns.Add("AvgDownSpeed", typeof(int));
            foreach (var item in _data)
            {
            
                dt.Rows.Add(new object[] { 
                        item .AvgDownSpeed,item.MaxDownSpeed,item.MinDownSpeed,
                        item.MinUpSpeed,item.AvgUpSpeed,item.Datetime,item.MaxUpSpeed});
            }
            ReportDataSource _rpdata = new ReportDataSource("DataSet2", dt);  
            this.ReportViewer1.LocalReport.DataSources.Clear();
//清理原来数据源
            this.ReportViewer1.LocalReport.DataSources.Add(_rpdata);//绑定新数据源
            ReportViewer1.LocalReport.Refresh();//刷新
            
            }
           

        }