I'm currently working on a project where I need to create a "dashboard" which can be exported as pdf. I wanted to use Rotativa but as our application uses .NET framework 4.0 it's not possible. So I found the NReco PdfGenerator.
Now that's the code how I create the PDF result:
var ViewAsString = RenderViewAsString("~/Views/QMetrics/StandardDashboard.cshtml", viewModel);
var htmlToPdf = new NReco.PdfGenerator.HtmlToPdfConverter();
htmlToPdf.PageWidth = 1600;
htmlToPdf.PageHeight = 900;
var pdfBytes = htmlToPdf.GeneratePdf(ViewAsString);
FileResult FileResult = new FileContentResult(pdfBytes, "application/pdf");
FileResult.FileDownloadName = "Dashboard-" + viewModel.ProjectName + "-" +
DateTime.Now.ToString() + "-.pdf";
return FileResult;
It successfully creates the PDF page with all the content that comes from the backend (Project information, and so on) but the page looks very ugly. On the original page I have 2 columns and on the PDF page it puts everything in one column. I tried a few different page sizes and I also changed the layout to be non-responsive but nothing has changed.
My first suggesstion was that the referenced CSS and JS files are not included when the PDF get's created, so I copied all the stuff that comes from external files (bootstrap, Chart.js) and pasted it directly in the .cshtml file. But nothing changed at all. My Chart is not rendering/loading and the missing CSS stuff is still not there.
On the NReco PDFGenerator website they say that it supports complex CSS code and also javascript code so I don't really understand why this is not working.
Has anyone here experiences with NReco or can someone recommend something else that works for .NET 4.0?
NReco PdfGenerator internally uses wkhtmltopdf tool, so you can check it and its options.
Regarding 2 columns: if you don't use flex/grid layout everything should work fine. Possibly you need to disable wkhtmltopdf smart shrinking logic (enabled by default) and define web page 'window' size explicitely (with "--viewport-size 1600" option).
Regarding CSS and charts: you need to check that CSS files could be accessed by wkhtmltopdf, simplest way to do that is running wkhtmltopdf.exe from the command line and check console log output (or, handle PdfGenerator's "LogReceived" event in C#). For Chart.js ensure that chart container div has explicit width (not in %), and that there are no js errors (you can get them in console by specifying "--debug-javascript" option). If your js code uses 'bind' method you have to include polyfill as WebKit engine version used in wkhtmltopdf doesn't support 'bind'.
Related
I bought a website template that has a scrolling photo gallery. As it came, the images are static in the fla file itself. I would like to edit the fla and load images dynamically. Ideally from MSSQL. I'm using VS2010, C# webforms, and SQL Server 2008 R2.
Are there any code snippets or tutorials or general guidance on how to do this? I do have a CS3 disc with Flash on it I can use for editing.
You can use a Loader + URLRequest, something like: (untested code)
var imgLoader:Loader = new Loader();
imgLoader.contentLoaderInfo.addEventListener(Event.COMPLETE, imageHasBeenLoaded);
imgLoader.load(new URLRequest("imagePath/from/database.jpg"));
public function imageHasBeenLoaded(e:Event) {
//Get the loaded bitmap image, do what you want with it from here.
var img:Bitmap = Bitmap(e.target.content);
}
Of course you would also want to feed the file paths to flash, either by FlashVars or by hitting a web service type of page (or xml file) via a Flash URLLoader + URLRequest. I prefer an xml file myself.
I'm currently using an html embed tag to display a pdf file that is saved on the local server. Is there a wayo to display a pdf file on my page without having to save it to the local file system of the server? I just wand to pass it to the view from the controller in such a way that it can be displayed as a pdf in the page without having it stored on the file system directly.
Alternatively, is there a way to call a method to delete the pdf file from the server once the user has navigated away from the page they are viewing? How do I tell if th euser has navicated away from the page and how do i cause that to trigger a method that will delete the file?
I created a MVC class called PdfResult that returns a byte array as a PDF file.
The purpose is as follows (can't upload the source code, sorry):
PdfResult inherits from FileStreamResult
Set the Content-Type header to application/pdf
Set the Content-Disposition to either attachment or inline, and set an appropriate file name
Convert your data to a Stream -- if your data is a byte array, then write it to a MemoryStream.
See https://stackoverflow.com/a/16673120/272072 for a good example of how to do this.
Then, your embed code just needs to point to the action method, as if it was a PDF file.
Here's an example:
public ActionResult ShowPdf() {
// Note: the view should contain a tag like <embed src='MyController/GetPdf'>
return View();
}
public ActionResult GetPdf() {
byte[] pdfBytes = dataRepo.GetPdf(...);
return new PdfResult(pdfBytes, "Filename.pdf", false) ;
}
Here is a link to a CodeProject article and code sample titled Download and Upload Images from SQL Server via ASP.NET MVC. This gives an example of an efficient method to stream content to and from SQL Server via MVC.
You can easily adapt the code to stream your PDF file downloads.
UPDATE
The article uses a DataReader, but it can easily be adapted to Linq2Sql or EF. As an example, here is the Read method where I am reading from the database and copying to the stream:
public override int Read(byte[] buffer, int offset, int count)
{
result = _attachments.ExecuteStoreQuery<byte[]>(
"SELECT SUBSTRING(AttachmentBytes, " + position.ToString() +
", " + count.ToString() + ") FROM Attachments WHERE Id = {0}",
id).First();
var bytesRead = result.Length;
Buffer.BlockCopy(result, 0, buffer, 0, bytesRead);
position += bytesRead;
return (int)bytesRead;
}
You can read the PDF as a bytestream from the database and save it to the http response stream. If you have set the content type correctly to application/pdf, then the browser will load the document in the PDF plugin.
Update (14/Oct/2011): You need to write the bytestream to the Response.OutputStream object. How you create and write the byte stream is dependent on how you have stored in the database and how you are retrieving it. The following code snippet is from an article we have on our website - Generate PDF Forms In ASP.NET Using PDFOne .NET v3.
// Get the page's output stream ready
Response.Clear();
Response.BufferOutput = true;
// Make the browser display the forms document
// using a PDF plug-in. (If no plug in is available,
// the browser will show the File -> Save As dialog box.
Response.ContentType = "application/pdf";
// Write the forms document to the browser
doc.Save(Response.OutputStream);
doc.Close();
doc.Dispose();
The doc object is from our component. You need not use that. This code snippet is only for your understanding. For your requirement, you may have to something like bytestream.save(Response.OutputStream) I guess. BTW, this code is for ordinary ASP.NET, not MVC.
DISCLAIMER: I work for Gnostice.
If you want to create the PDF 100% dynamically, you would generate it completely in memory then stream it out directly to the requesting web browser without saving it as a file. This is very easy to do with the right tools. I would recommend AspPDF from Persits.com as a way to do this very easily. Take a look at their online documentation to see how simple this is to do without creating a bunch of rendered PDF files all over your server.
If you cannot do something like that, then simply incorporate a process to cleanup your "expired" PDF files from your server's filesystem based on their age. For example, after you have created your local PDF file, you just look through the folder containing your temporary PDF's and delete any you find over a certain age. You cannot reliably tell if or when a user has navigated away from your page or site.
For the first part of your question, like mentioned in the comments, use some type of stream object to pass the PDF data around. Right now, you are streaming the file to the local file system, then streaming it once again to the embedded tag for display. Just do away with the intermediate step of saving to the file system, and do the whole thing in memory (although, that's not really a model of efficiency, and might not scale well).
Regarding the second part of your question, that's not as straightforward. MVC really has no concept of state (viewstate, etc.), so it doesn't have events that can be fired from a state change (say, navigating away from a page).
You could use Javascript to detect a user navigating away from your page (windows.onunload), that calls a (C#/VB) method to remove the file from the file system. You would probably have to use AJAX to communicate back to the server, using an HTTP POST method, and have something listening at that URL endpoint to fire your method that removes the file.
I am creating a HTML catalog of movies, and then converting it to PDF. I was using EO.Pdf, and it worked for my small test sample. However, when I run it against the entire list of movies, the resulting HTML file is nearly 8000 lines, and 7MB. EO.Pdf times out when attempting to convert it. I believe it is a limitation of the free version, as I can copy the entire HTML and paste it into their online demo and it works.
I am looking for an alternative to use. I am not good with command line, or running external programs, so I would prefer something I can add to the .NET library and use easily. I will admit that the use of EO.Pdf was easy, once I added the dll to the libarary and added the namespace, it took one line of code to convert either the HTML Code, or the HTML file into a PDF. The downsides I ran into were that they had a stamp on every page (in 16pt font) with their website on it. It also wouldn't pick up half of my images, not sure why. I used a relative URL in the HTML file to the images, and I created the PDF in the same dir as the HTML file.
I do not want to re-create the layout in a PDF, so I think something like iTextSharp is out. I've read a bit about something called like wkhtmltopdf or something strange like that. It sounded good, but needed a wrapper, and I have no clue how to accomplish that, or use it.
I would appreciate suggestions with basic instructions how to use them. Either a library and a couple lines on how to use it. Or if you can tell me how to setup/use the wkhtmltopdf I would be extremely greatful!
Thanks in advance!
I'm using wkhtmltopdf and I'm very happy with it. One way of using it:
Process p = new Process();
p.StartInfo.CreateNoWindow = true;
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.FileName = "wkhtmltopdf.exe";
p.StartInfo.Arguments = "-O landscape <<URL>> -";
p.Start();
and then you can get a stream:
p.StandardOutput.BaseStream
I used this because I needed a stream, of course you can invoke it differently.
Here is also a discussion about invoking wkhtmltopdf
I just saw, that someone is implementing a c# wrapper for wkhtmltopdf. I haven't tested it, but may be worth a look.
After much searching I decided to use HiQPdf. It was simple to use, fast enough for my needs and the price point was acceptable to me.
var converter = new HiQPdf.HtmlToPdf();
converter.Document.PageSize = PdfPageSize.Letter;
converter.Document.PageOrientation = PdfPageOrientation.Portrait;
converter.Document.Margins = new PdfMargins(15); // Unit = Points
converter.ConvertHtmlToFile(htmlText, null, fileName);
It even includes a free version if you can keep it to 3 pages.
http://www.hiqpdf.com/free-html-to-pdf-converter.aspx
And no, I am in no way affiliated with them.
I recommend ExpertPdf.
ExpertPdf Html To Pdf Converter is very easy to use and it supports the latest html5/css3. You can either convert an entire url to pdf:
using ExpertPdf.HtmlToPdf;
byte[] pdfBytes = new PdfConverter().GetPdfBytesFromUrl(url);
or a html string:
using ExpertPdf.HtmlToPdf;
byte[] pdfBytes = new PdfConverter().GetPdfBytesFromHtmlString(html, baseUrl);
You also have the alternative to directly save the generated pdf document to a Stream of file on the disk.
I have a long javascript in a string and programatically using RegisterClientScriptBlock, I add it to my page.
Is there any way to have the intellisense detect my javascript inside the string?
Code:
string Script0 =
#"
function dummy()
{
}
var PTRValues = new Array();
...
...
..
";
this.Page.ClientScript.RegisterClientScriptBlock(this.GetType(), "myCustomScriptBlock", Script0, true);
No, you can't get intellisense inside the JS string. The IDE doesn't know this particular string is JS.
If it's long don't put it in the *.cs file. Instead store it in a *.js. If you really want you can load the file into memory at runtime and serve it embedded in the html instead of referenced.
Unfortunately, this is not possible.
The best solution is to make put the code separate .js file, then write the following:
Page.ClientScript.RegisterClientScriptBlock(
GetType(),
"myCustomScriptBlock",
File.ReadAllText(myJSFilePath),
true
);
For optimal performance, you should read it only once, then store in in the cache.
Ok, these guys are getting close...
Don't EVER embed scripts in code. Always embed as resource or for prototyping and develepment use ClientScript to render a <script/> tag and reference a .js file.
There are just too many reasons wny you would not want to embed script in code to list. google it.
What you are after is to render some javascript from the codebehind via ClientScript and you would like design time intellisense support?
Ok,
To get intellisense you will need a .js of some kind. The approach I suggest, to promote maintainability and prevent dupe scripts that can get out of sync is:
create an EMPTY file called myScript.js.
create another script containing your code named myScript-vsdoc.js
mark myScript-vsdoc.js as embedded resource and serve it as and embedded web resource
meanwhile, back in the IDE, add a script tag pointing to myScript.js, which is an EMPTY file
press SHIFT-CTRL-J and bingo, you have intellisense for your embedded script, your embedded script is in a source file that is editable and discoverable and you have no duplication.
That is how i do it.
I learned we should assgin a .bin file to the Source attribute of Siverlight MultiScaleImage. For example, I learned from here (refers to code sample in section Anonymous Methods for Events),
http://www.soulsolutions.com.au/Blog/tabid/73/EntryId/410/Silverlight-Deep-Zoom-Sample-Code-Part-2.aspx
But I have tried using export function of Deep Zoom Composor will never generate .bin file. Here are my screen snapshots. Any ideas what is wrong?
(I am using VSTS 2008 + .Net 3.5 + C#.)
The MultiScaleImage control's Source property can be set in a couple different ways. If you're setting it in XAML, you can point to the dzc_output.xml file (located in the GeneratedImages folder) directly like so:
<MultiScaleImage x:Name="Foo" Source="/GeneratedImages/dzc_output.xml" />
You can also set it in code, you you need to take the extra step of assigning it as a DeepZoomImageTileSource:
Foo.Source = new DeepZoomImageTileSource(
new Uri("/GeneratedImages/dzc_output.xml", UriKind.Relative));
Hope that helps!
Inside the GeneratedImages folder is an xml file called dzc_output.xml that should be the new end-point for a MultiScaleImage.
With the new versions of DeepZoomComposer, the bin file format has been replaced with this new xml file.