Hi,

I am totaly new to this product, sorry it the question is duplicate, but I didn't find similar question in the forum. I was wondering why is everything static when I want to convert html to pdf. Especially those methods:

HtmlToPdf.Options.AfterRenderPage += On_AfterRenderPage;
and
HtmlToPdf.ConvertHtml(data, outputPath);

How can I be sure, that when doing more conversions simultaneously, that everything works correctly? What if I want to create two different handlers for every conversion and run both at a same time?

Thank you very much for your help!
L.K.

Thank you for your fast answere! Yeah, this exactly fits to my observations how it behaves inside of Task.Run... It is not optimal, but I think we can go with this...

Hi,

We are not sure what you meant by "there is no thread separation guaranteed". The thread separation are guaranteed because each thread uses their own copy of values. If you do not like the static flavor, you can use one of the flavor that takes an HtmlToPdfOptions argument such as this one:

http://www.essentialobjects.com/doc/4/eo.pdf.htmltopdf.converturl_overload_8.aspx

The code would be something like this:



In either case, you should not have problem regardless you use the old days Thread class or the new fancy Tasks and async feature. Tasks and async feature are built on top of thread pool and they do not change anything beneath. Thus using Tasks or await (these are just syntax candy) makes no difference from the converter point of view. So there is no need for you to wrap your code inside "single thread". In another word, if you run into problems when using .NET 4.5's Tasks and async, the problem would be somewhere else.

One thing you do need to keep in mind is that converting HTML to PDF is a rather expensive task --- it is both network intensive (during the load stage) and CPU intensive (during the conversion stage). So it's not that you have more thread it will run faster. For example, if your system only have a single CPU, then it would definitely help if you have 2 threads ---- while one is waiting on the network the other can use the CPU. However if you have 10 threads, then they will just be over competing and constantly rob each other off. In that case you will start to get time out errors and you are basically overloading your server and that's not an issue can be resolved by multi-threading.

Thanks!

I see. Yes you are right. If you use the static options, the only way to guarantee you get the correct options is to put the code that sets the option and HtmlToPdf.ConvertUrl calls inside the same task function. If one is inside the task function and another is outside of the task function, it's almost certain that they will get mixed up. In any case, the overloads with the options argument will probably make things easier since the value is passed as argument instead of relying on thread static variables.

Thanks!