Here is the problem I am trying to solve. I have a computer (actually it is a piece of medical equipment running windows 7 and does have access to internet explorer.) This computer is creating a large data file that is many megabytes in size (sometimes over a few hundred MB.)
Because it is considered medical equipment, I can't load software onto the computer. What I need to do is write a web application that does a file upload. That part is pretty easy. Create the form, upload the file and handle the transfer and saving of the file on the server.
The part that I can't figure out is how can I (from within the html page /web browser) do a checksum on the file as it is on the computer hard drive so that I can compare it to a checksum on the same file once it is uploaded and stored on the server? Because it is patient-related data that is subject to data retention policies, accessibility for legal and future medical needs, etc. I need to be 100% certain the file was not corrupted during the transfer. Given the quality of the data connections in various hospitals, there could be problems.
Any ideas would be appreciated...