Default.aspx.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Web.UI;
using DevExpress.Web;
using DevExpress.XtraRichEdit;

public partial class _Default : Page {
	protected void Page_Load(object sender, EventArgs e) {
		if ( !String.IsNullOrEmpty(Request["loadFile"]) )
			WritePdfToResponse(Request["loadFile"]);
	}

	private void WritePdfToResponse(string fileName) {
		object uploadedFileBytes = Page.Session["UploadedFile"];
		if ( uploadedFileBytes == null )
			return;
		MemoryStream stream = MemoryStreamHelper.FromBytes(uploadedFileBytes);
		Page.Session["UploadedFile"] = null;
		if ( stream == null )
			return;
		stream.WriteTo(Page.Response.OutputStream);
		Page.Response.ContentType = "application/pdf";
		Page.Response.HeaderEncoding = System.Text.Encoding.UTF8;
		Page.Response.AddHeader("Content-Disposition", String.Format("attachment; filename={0}.pdf", Path.GetFileNameWithoutExtension(fileName)));
		Page.Response.End();
	}

	protected void ASPxUploadControl_FileUploadComplete(object sender, DevExpress.Web.FileUploadCompleteEventArgs e) {
		ASPxUploadControl uploadControl = (ASPxUploadControl)sender;
		UploadedFile uploadedFile = uploadControl.UploadedFiles[0];
		e.CallbackData = Request.Url.AbsoluteUri.Replace(Request.Url.Query, String.Empty) + String.Format("?loadFile={0}", uploadedFile.FileName);
		try {
			Stream pdfStream = ConvertToPdf(uploadedFile.FileContent, uploadedFile.FileName);
			Session["UploadedFile"] = MemoryStreamHelper.ToBytes(pdfStream);
		} catch ( Exception ex ) {
			e.ErrorText = ex.Message;
			e.IsValid = false;
		}
	}

	private Stream ConvertToPdf(Stream stream, string fileName) {
		RichEditDocumentServer server = new RichEditDocumentServer();
		server.LoadDocument(stream, FileExtensionHelper.GetDocumentFormat(fileName));
		MemoryStream memoryStream = new MemoryStream();
		server.ExportToPdf(memoryStream);
		return memoryStream;
	}
}

public static class MemoryStreamHelper {
	public static byte[] ToBytes(Stream stream) {
		stream.Position = 0;
		byte[] buf = new byte[stream.Length];
		stream.Read(buf, 0, (int)stream.Length);
		return buf;
	}

	public static MemoryStream FromBytes(object bytes) {
		byte[] buf = bytes as byte[];
		MemoryStream stream = new MemoryStream(buf);
		return stream;
	}
}

public static class FileExtensionHelper {
	private static Dictionary<string, DocumentFormat> useFormat = new Dictionary<string, DocumentFormat>();

	static FileExtensionHelper() {
		useFormat.Add("txt", DocumentFormat.PlainText);
		useFormat.Add("docx", DocumentFormat.OpenXml);
		useFormat.Add("doc", DocumentFormat.Doc);
		useFormat.Add("rtf", DocumentFormat.Rtf);
		useFormat.Add("odt", DocumentFormat.OpenDocument);
		useFormat.Add("htm", DocumentFormat.Html);
		useFormat.Add("mht", DocumentFormat.Mht);
		useFormat.Add("epub", DocumentFormat.ePub);
	}

	public static DocumentFormat GetDocumentFormat(string fileName) {
		DocumentFormat format;
		string extension = Path.GetExtension(fileName).TrimStart('.').ToLower();
		if ( String.IsNullOrEmpty(extension) )
			return DocumentFormat.Undefined;
		if ( useFormat.TryGetValue(extension, out format) )
			return format;
		return DocumentFormat.Undefined;
	}
}