在运行时创建

我用下面的代码在运行时创建一个简单的条形图，然后将其作为图像导出到用户的计算机。

    [HttpGet]
    public HttpResponseMessage Get([FromBody]ScoreByLocation sblx)
    {
        sbl.ImageWidth = 400;
        sbl.ImageHeight = 300;
        HttpResponseMessage msg = null;
        try
        {
            WebChartControl sideBySideBarChart = new WebChartControl();
            sideBySideBarChart.Width = sbl.ImageWidth;
            sideBySideBarChart.Height = sbl.ImageHeight;
            DevExpress.XtraCharts.Series series1 = new DevExpress.XtraCharts.Series("Side-by-Side Bar Series 1", ViewType.Bar);
            sideBySideBarChart.Series.Add(series1);
            DataTable dt = new DataTable();
            DataColumn dc;
            dc = new DataColumn();
            dc.ColumnName = "Name";
            dt.Columns.Add(dc);
            dc = new DataColumn();
            dc.ColumnName = "Age";
            dt.Columns.Add(dc);
            (other data creation here..)
            sideBySideBarChart.DataSource = dt;
            series1.ArgumentScaleType = ScaleType.Numerical;
            series1.ArgumentDataMember = "Argument";
            series1.ValueScaleType = ScaleType.Numerical;
            series1.ValueDataMembers.AddRange(new string[] { "Value" });
            sideBySideBarChart.DataBind();
            //save to memory stream and then to byte array
            byte[] b = null;
            using (MemoryStream ms = new MemoryStream())
            {
                ((IChartContainer)sideBySideBarChart).Chart.ExportToImage(ms, System.Drawing.Imaging.ImageFormat.Png);
                b = ms.ToArray();
            }
            msg = Request.CreateResponse(HttpStatusCode.OK);
            msg.Content = new ByteArrayContent(b);
            msg.Content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("image/png");
            msg.Content.Headers.ContentDisposition = new System.Net.Http.Headers.ContentDispositionHeaderValue("attachment");
            msg.Content.Headers.ContentDisposition.FileName = "report.png";
        }
        catch (Exception ex)
        {
            msg = Request.CreateErrorResponse(HttpStatusCode.InternalServerError, ex.Message.ToString());
        }
        return msg;
    }
}

}

由于某种原因，当我运行这段代码时，返回的图形是空白的。我能够查看图像，它具有我想要的所有属性(即高度，宽度等)，但由于某种原因，没有轴或条或其他数据。如果有人能指出我做错了什么，我将不胜感激。

谢谢