In this example I want to leverage the HTML to PDF conversion functionality implemented in our RadContols for WPF suite. This can be done quite easily, just follow my lead:
I am first going to start a new Telerik C# RadControls Web Application. I will make sure that the Telerik.Web.UI assembly reference points to the latest Q1 2013 version (2013.1.220.40), or you could use a version of RadControls for ASP.NET AJAX released after Q1 2013.
Next, I will start working through the default.aspx page. First, I will add an instance of RadEditor with a couple of ExportSettings configurations.
The ExportButton click handler should look like the following code.
using System;
using Telerik.Web.UI;
using Telerik.Web.UI.Editor.Export;
using Telerik.Windows.Documents.Model;
using Telerik.Windows.Documents.FormatProviders.Pdf;
using Telerik.Windows.Documents.FormatProviders.Html;
using System.Threading;
using System.Net;
using System.IO;
public class TelerikPdfExportTemplate: RadEditorExportTemplate
{
public TelerikPdfExportTemplate (RadEditor radEditor) : base(radEditor)
{
}
//no need to initialize the XmlContent
protected override void InitializeXmlContent()
{
}
protected override string GenerateOutput()
{
string output = "";
var thread = new Thread(() =>
{
PdfFormatProvider provider = new PdfFormatProvider();
RadDocument document = this.ImportDocument();
this.ProcessDocument(document);
byte [] buffer = provider.Export(document);
output = ResponseWriteEncoding.GetString(buffer);
});
thread.SetApartmentState(ApartmentState.STA);
thread.Start();
thread.Join();
return output;
}
private RadDocument ImportDocument()
{
HtmlFormatProvider provider = new HtmlFormatProvider();
provider.ImportSettings.LoadImageFromUrl += ImportSettings_LoadImageFromUrl;
return provider.Import(editor.Content);
}
void ImportSettings_LoadImageFromUrl(object sender, LoadImageEventArgs e)
{
//This ensures images are properly loaded from url.
WebRequest req = WebRequest.Create(e.Url);
WebResponse response = req.GetResponse();
Stream imageStream = response.GetResponseStream();
using (var memoryStream = new MemoryStream())
{
imageStream.CopyTo(memoryStream);
string extension = Path.GetExtension(e.Url);
e.ImageElement.Init(memoryStream, extension);
e.ImageElement.Tag = e.Url;
e.Handled = true;
}
}
private void ProcessDocument(RadDocument document)
{
document.LayoutMode = DocumentLayoutMode.Paged;
//This reduces the space added by RadDocument's model before and after table elements.
RadDocumentEditor documentEditor = new RadDocumentEditor(document);
var tables = documentEditor.Document.EnumerateChildrenOfType<Table>();
foreach (var table in tables)
{
Paragraph previousParagraph = table.PreviousSibling as Paragraph;
if (previousParagraph != null && previousParagraph.IsEmpty)
{
documentEditor.Document.CaretPosition.MoveToEndOfDocumentElement(previousParagraph);
documentEditor.ChangeParagraphSpacingAfter(0);
documentEditor.ChangeFontSize(2);
}
Paragraph nextParagraph = table.NextSibling as Paragraph;
if (nextParagraph != null && nextParagraph.IsEmpty)
{
documentEditor.Document.CaretPosition.MoveToEndOfDocumentElement(nextParagraph);
documentEditor.ChangeParagraphSpacingAfter(0);
documentEditor.ChangeFontSize(2);
}
}
}
protected override string ContentType
{
get { return "application/pdf"; }
}
protected override string FileExtension
{
get { return ".pdf"; }
}
protected override ExportType ExportType
{
get { return ExportType.Pdf; }
}
}