一个简单的报表问题


        CommonClass com = new CommonClass();
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                DataSet ds = com.GetDataSet("select userid,username from userinfo","userinfo");
                ReportDataSource RDS = new ReportDataSource("userinfo", ds.Tables["userinfo"]);                ReportViewer1.Visible = true;
                ReportViewer1.LocalReport.DataSources.Clear();
                ReportViewer1.LocalReport.DataSources.Add(RDS);
                //ReportViewer1.LocalReport.SetParameters("userid");
                ReportViewer1.LocalReport.Refresh();
            }        }
aspx代码        <rsweb:ReportViewer ID="ReportViewer1" runat="server" >
        </rsweb:ReportViewer>不报错，又不显示··为什么，郁闷！！dataset是有数据的！！！1