How to launch MS excel from Blazor WASM?

Nitesh 21

Hi,

I have a csv file stream which i have saved to temporary file, and i want to launch MS excel with this file so that user can do any update on the file and save it if required.
I tried using Interop methods but in WASM i am getting error that "com operation is not supported in this platform".
Please let me know if anyone has tried this before or is this even possible to do with Blazor WASM applications.

Thanks,
Nitesh

AgaveJoe 26,191 Reputation points

2022-05-06T11:42:32.263+00:00

The Excel file must be on the server. First, download the file using a web application like Web API. The user makes changes to the file and uses the Blazor interface to upload the file to the server.
Nitesh 21 Reputation points

2022-05-06T13:19:47.633+00:00

Hi AgaveJoe,

Thank you for sharing your solution, although I am trying to achieve is OPEN the MS EXCEL loaded with the csv file data.
I know we can launch the EXCEL from c# code, but below code doesn't work in WASM:-

this.Application.Workbooks.Open(@"C:\Test\YourWorkbook.xlsx");

thanks,
Nitesh
AgaveJoe 26,191 Reputation points

2022-05-06T13:29:33.887+00:00

The file MUST be stored the server. Browser security does not allow opening a local file. Again, you can "stream" the file from the server to the Blazor WASM. Otherwise, you'll need to write a Windows application not a web application.
Nitesh 21 Reputation points

2022-05-06T14:10:51.837+00:00

Oh got it,

One question when you say: "you can "stream" the file from the server to the Blazor WASM", does this mean i can send this stream to excel application from Blazor wasm app.

Regards,
Nitesh
Brando Zhang-MSFT 2,956 Reputation points Microsoft Vendor

2022-05-09T02:03:25.91+00:00

Hi @Anonymous ,

It means you could write another endpoint which contains that excel and could return that excel to the client. Like API or a static file path which could be accessed by using the url. Then the blazor could access that path.
Nitesh 21 Reputation points

2022-05-09T07:00:58.307+00:00

HI @Brando Zhang-MSFT ,

thanks for sharing the details,

regards,
nitesh