Warning that a file exists(file upload)

[Christer Claesson]

Hello there I'm building an application that will allow users to upload files to an online file manager of sorts. I've chosen to store the files in a database and so far I'm satisfied with the solution. However I've encountered a problem with the file upload. I'm using the built in file upload in asp.net 2.0. I would like to warn the user that a file with that name already exists and prompt a popup with an Ok(to overwrite) and Cancel(abort upload). This is the classic client/server side problem though I guess, but even if I've looked around for a solution for a while I have not found any. And I'm sure I'm not the first with this problem. Any suggestions/links on how to solve this? Regards Christer Claesson

[g00fyman]

The way i achieve this is to use my asp:message box (a custom control) and return a warning to the user, because the control is server based i can act on the events at the server and not have to rely on javascript, the other way is just to rename the file (and, if you choose) maintain a mapping in your database. the mapping is extra overhead and not really required unless you must have the filename they uploaded. regs, g00fy

[Christer Claesson]

Thank you for your reply. This custom control, is it open source and avaliable for others? Due to space issue I would like to overwrite files and not store double(or more) copies of each file. Regards Christer

[g00fyman]

it is still in beta, but will be available soon for a small cost. the other option you have is to do a quick if(File.Exists()) { } and if true then display a button on the page that confirms the overwrite of the file. This way on the first postback you could upload the file and name it like ~filename.ext. If the answer is no then either force them to click a No button and delete the temp file or just delete it on next file upload and check. the latter option would require maintaining a list of files to be deleted, else you could have concurrency problems if this is a multi user application. regards, g00fy