C# fetch a text from a website and render it as image

using System;
using System.Web;
using System.Drawing;
using System.IO;
using System.Net;
using System.Text;
using System.Drawing.Drawing2D;
using System.Drawing.Text;

public partial class _Default : System.Web.UI.Page
{
    private static HttpWebRequest request;
    private static HttpWebResponse response;
    private static string urlToFetch = "http://www.staatsschulden.at/";
    
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!this.IsPostBack)
        {
            this.SetImage();
        }
    }

    protected byte[] GetImageBytes(System.Drawing.Image image)
    {
        byte[] byteArray = new byte[0];
        using (MemoryStream stream = new MemoryStream())
        {
            image.Save(stream, System.Drawing.Imaging.ImageFormat.Jpeg);
            stream.Close();

            byteArray = stream.ToArray();
        }

        return byteArray;
    }

    protected void SetImage()
    {
        string finder = "<span class=\"money\" id=\"debt\">";
        char[] trimchars = "\r\n".ToCharArray();       
        string uriResponse = this.FetchFromUri(urlToFetch, "");
        int schuldidx = uriResponse.IndexOf(finder);
        string rest = uriResponse.Substring(schuldidx + finder.Length);
        int endschuld = rest.IndexOf("</span>");
        rest = rest.Substring(0, endschuld).Trim(trimchars);
        Bitmap b = this.CreateImage(rest);
        // b.Save(Server.MapPath("staatsschulden.jpeg"), System.Drawing.Imaging.ImageFormat.Jpeg);
        byte[] bytes = GetImageBytes(b);

        Response.BinaryWrite(bytes);
    }

    private string FetchFromUri(string requestUrl, string requestParameter)
    {
        string fetched = "";
       
        request = (HttpWebRequest)WebRequest.Create(requestUrl);

        byte[] parameter = Encoding.UTF8.GetBytes(requestParameter);
        request.Method = "POST";
        request.ContentType = "application/x-www-form-urlencoded";
        request.ContentLength = parameter.Length;

        Stream requestStream = request.GetRequestStream();
        requestStream.Write(parameter, 0, parameter.Length);
        requestStream.Close();

        //Holt sich die Antwort
        response = (HttpWebResponse)request.GetResponse();

        Stream responseStream = response.GetResponseStream();
        StreamReader streamReader = new StreamReader(responseStream);
        fetched = streamReader.ReadToEnd();
        streamReader.Close();
        responseStream.Close();
       
        return fetched;
    }


    private Bitmap CreateImage(string s)
    {
        Bitmap b = new Bitmap(1, 1);

        int width = 0;
        int height = 0;

        Font font = new Font("Trebuchet", 16, System.Drawing.FontStyle.Bold,
            System.Drawing.GraphicsUnit.Pixel);
        Graphics g = Graphics.FromImage(b);
        width = (int)g.MeasureString(s, font).Width;
        height = (int)g.MeasureString(s, font).Height;
        b = new Bitmap(b, new Size(width, height));
        g = Graphics.FromImage(b);

        g.Clear(Color.White);
        g.SmoothingMode = SmoothingMode.AntiAlias;
        g.TextRenderingHint = TextRenderingHint.AntiAlias;
        g.DrawString(s, font, new SolidBrush(Color.BlueViolet), 0, 0);
        g.Flush();

        return (b);
    }
}