问题
I'm using EPPLUS to allow users to download data to Excel. However, I'd like to add a feature wherein they can just choose to print this data rather than download it. Can we issue a print command from EPPLus?
回答1:
It is a web app
Ah, so there's the main problem... You know, even if EPPlus had a method for printing, it wouldn't help you, because it would try to trigger a printing dialog on the server-side, but you need to send the file to the client over the internet. So I'm afraid the answer is no, the client surely has to download the file either way to be able to print it.
Furthermore, xlsx can't be that easily opened in the web browser (compared to pdf for instance), so the solution to somehow trigger a printer dialog on the clients pc will be a tiny bit difficult. C# can't trigger anything over the internet with asp.net because of the security problems and I'm not really sure if javascript has enough permissions to open an application for Excel file and start the printing process..
Maybe your solution would be to create a PDF file instead of XLSX, send it to the client as a part of the website/response and use javascript to print the file. PDF can be opened in most browsers nowadays and we have a nice js function printWithDialog(). I believe this doesn't work for xls and it certainly doesn't fulfil your requirement "without download". The client has to have the access to the file before he can print it, you can't overcome this.
来源：https://stackoverflow.com/questions/15814447/print-command-in-epplus