How to set HtmlSaveOptions to save html and resources to stream using Aspose PDF - aspose

Question

I am trying to use Aspose.PDF to load PDF from databases, convert it to HTML and render them to our web page.I want to know if we can save both the document and the resource to stream since current example in the document of Aspose.PDF saves css and images to a local path. I have tried this but the is and error that Aspose.Pdf.SaveFormat.Html is not supported.
Aspose.Pdf.Document PDFDocument = new Aspose.Pdf.Document(PDFStream);
MemoryStream HTMLStreamFromPDF = new MemoryStream();
PDFDocument.Save(HTMLStreamFromPDF, Aspose.Pdf.SaveFormat.Html);
If it can be done, how to write the parameters of CustomResourceSavingStrategy, CustomCssSavingStrategy, and CustomStrategyOfCssUrlCreation of HtmlSaveOptions. I am sorry that I am not quite familiar with delegate in C#
Thanks!

Answer 1

Finally found a way to save all files to stream.
MemoryStream HTMLStreamFromPDF = new MemoryStream();
List<MemoryStream> ResourseStreamList = new List<MemoryStream>();
List<string> ResourceNameList = new List<string>();
MemoryStream CSSStream = new MemoryStream();
Aspose.Pdf.HtmlSaveOptions saveOptions = new Aspose.Pdf.HtmlSaveOptions();
CustomResourcesProcessingBind customResourcesProcessingBind = new CustomResourcesProcessingBind((_1) => CustomResourcesProcessing(ResourseStreamList,ResourceNameList, RequestURL, _1));
saveOptions.CustomResourceSavingStrategy = new Aspose.Pdf.HtmlSaveOptions.ResourceSavingStrategy(customResourcesProcessingBind);
CssUrlCreationCustomStrategyBind cssUrlCreationCustomStrategyBind = new CssUrlCreationCustomStrategyBind((_1) => CssUrlCreationCustomStrategy(RequestURL, _1));
saveOptions.CustomStrategyOfCssUrlCreation = new Aspose.Pdf.HtmlSaveOptions.CssUrlMakingStrategy(cssUrlCreationCustomStrategyBind);
CustomCssSavingProcessingBind customCssSavingProcessingBind = new CustomCssSavingProcessingBind((_1) => CustomCssSavingProcessing(CSSStream, _1));
saveOptions.CustomCssSavingStrategy = new Aspose.Pdf.HtmlSaveOptions.CssSavingStrategy(customCssSavingProcessingBind);
saveOptions.HtmlMarkupGenerationMode = Aspose.Pdf.HtmlSaveOptions.HtmlMarkupGenerationModes.WriteOnlyBodyContent;
PDFDocument.Save(HTMLStreamFromPDF, saveOptions);
private delegate string CustomResourcesProcessingBind(Aspose.Pdf.SaveOptions.ResourceSavingInfo resourceSavingInfo);
private static string CustomResourcesProcessing(List<MemoryStream> ResourseStreamList, List<string> ResourceNameList, string RequestURL, Aspose.Pdf.SaveOptions.ResourceSavingInfo resourceSavingInfo)
{
MemoryStream newResource = new MemoryStream();
resourceSavingInfo.ContentStream.CopyTo(newResource);
ResourceNameList.Add(resourceSavingInfo.SupposedFileName);
ResourseStreamList.Add(newResource);
string urlThatWillBeUsedInHtml = RequestURL +"/"+ Path.GetFileName(resourceSavingInfo.SupposedFileName);
return urlThatWillBeUsedInHtml;
}
private delegate string CssUrlCreationCustomStrategyBind(Aspose.Pdf.HtmlSaveOptions.CssUrlRequestInfo requestInfo);
private static string CssUrlCreationCustomStrategy(string RequestURL,Aspose.Pdf.HtmlSaveOptions.CssUrlRequestInfo requestInfo)
{
return RequestURL + "/css_style.css";
}
private delegate void CustomCssSavingProcessingBind(Aspose.Pdf.HtmlSaveOptions.CssSavingInfo resourceInfo);
private static void CustomCssSavingProcessing(MemoryStream CSSStream, Aspose.Pdf.HtmlSaveOptions.CssSavingInfo resourceInfo)
{
resourceInfo.ContentStream.CopyTo(CSSStream);
}

Answer 2

Check the following sample code regarding how to use parameters CustomResourceSavingStrategy, CustomCssSavingStrategy and CustomStrategyOfCssUrlCreation of HtmlSaveOptions when converting from PDF to HTML.
static string _folderForReferencedResources;
static void Main(string[] args)
{
Document pdfDocument = new Document(#"F:\ExternalTestsData\input.pdf");
string outHtmlFile = #"F:\ExternalTestsData\output.html";
_folderForReferencedResources = #"F:\ExternalTestsData\resources\";
//-----------------------------------------------------
// 2)clean results if they already present
//-----------------------------------------------------
if (Directory.Exists(_folderForReferencedResources))
{
Directory.Delete(_folderForReferencedResources, true);
}
File.Delete(outHtmlFile);
//-----------------------------------------------------
// create HtmlSaveOption with tested feature
//-----------------------------------------------------
HtmlSaveOptions saveOptions = new HtmlSaveOptions();
saveOptions.CustomResourceSavingStrategy = new HtmlSaveOptions.ResourceSavingStrategy(Strategy_11_CUSTOM_SAVE_OF_FONTS_AND_IMAGES);
saveOptions.CustomCssSavingStrategy = new HtmlSaveOptions.CssSavingStrategy(Strategy_11_CSS_WriteCssToPredefinedFolder);
saveOptions.CustomStrategyOfCssUrlCreation = new HtmlSaveOptions.CssUrlMakingStrategy(Strategy_11_CSS_ReturnResultPathInPredefinedTestFolder);
using (Stream outStream = File.OpenWrite(outHtmlFile))
{
pdfDocument.Save(outStream, saveOptions);
}
}
private static void Strategy_11_CSS_WriteCssToPredefinedFolder(HtmlSaveOptions.CssSavingInfo resourceInfo)
{
if (!Directory.Exists(_folderForReferencedResources))
{
Directory.CreateDirectory(_folderForReferencedResources);
}
string path = _folderForReferencedResources + Path.GetFileName(resourceInfo.SupposedURL);
System.IO.BinaryReader reader = new BinaryReader(resourceInfo.ContentStream);
System.IO.File.WriteAllBytes(path, reader.ReadBytes((int)resourceInfo.ContentStream.Length));
}
private static string Strategy_11_CSS_ReturnResultPathInPredefinedTestFolder(HtmlSaveOptions.CssUrlRequestInfo requestInfo)
{
return "file:///" + _folderForReferencedResources.Replace(#"\", "/") + "css_style{0}.css";
}
private static string Strategy_11_CUSTOM_SAVE_OF_FONTS_AND_IMAGES(SaveOptions.ResourceSavingInfo resourceSavingInfo)
{
if (!Directory.Exists(_folderForReferencedResources))
{
Directory.CreateDirectory(_folderForReferencedResources);
}
string path = _folderForReferencedResources + Path.GetFileName(resourceSavingInfo.SupposedFileName);
// first path of this method is for saving of font
System.IO.BinaryReader contentReader = new BinaryReader(resourceSavingInfo.ContentStream);
System.IO.File.WriteAllBytes(path, contentReader.ReadBytes((int)resourceSavingInfo.ContentStream.Length));
string urlThatWillBeUsedInHtml = "file:///" + _folderForReferencedResources.Replace(#"\", "/") + Path.GetFileName(resourceSavingInfo.SupposedFileName);
return urlThatWillBeUsedInHtml;
}
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P.S. I am Social Media Developer at Aspose.