We're sorry Aspose doesn't work properply without JavaScript enabled.

Free Support Forum - aspose.com

Aspose Cells file validation

I created a txt file then I just changed the file extension into .xlsx, does Aspose cells detect that the file is not valid just like Aspose Word?

For file detection, you can refer to the following documents:

Do you want to detect that the file content does not match the suffix name?
FileFormatUtil.DetectFileFormat() will detect the file type by the content of the file, then you can compare the detected file type with extension.