I'm still rebuilding old ASP to new and iframing certain things that take up too much time.
I'm stuck at a search function that normally returns an excel file (browser asks save or open). the result page for this is now iframed but it does not seem to propagate the file anymore, so no more save-file popup.
I must add that this iframe is being filled through a custom httphandler that posts to the old pages based on certain criterie, the searchcriteria in this case.
does anyone have an idea on how I could make the excel propagate once again?
The way to ensure you get a save-file prompt and not a page, do the following:
Open the file in ASP
Send the MIME header for Excel
Stream out the file from ASP
You may also choose to hold the files outside of the web root so they cannot be downloaded directly.
Here are a few examples: 1 2 3
This may come in handy as well:
How to output an Excel *.xls file from classic ASP
It *seems* like a security issue. What happens if you open the URL which is being loaded in the IFrame in a new browser? To confirm it, you can try opening the URL, and see what happens.
Related
I have some Word files which need to have hyperlinks. The hyperlinks go to an htm file with an anchor, but that htm file isn't provided via a direct url for security reasons. Rather it is linking to a ashx handler file that retrieves the file and does an response.write to show the html file in the browser. Before it does this, though, it checks to back sure that there's a valid session, and if there isn't then it just redirects to the login page. This works fine when linking from within the ASP.Net site, but when I link to it from a local MSWord file, it apparently doesn't know there's a valid session (even though I've logged in in the browser), and redirects to the login page. Is there any way around this? For compatibility these Word documents need to be in Word 97-2003 format unfortunately...
No. This won't work.
Opening the word file outside of a browser and clicking on the link is going to start a brand new session; regardless of whether you currently have a browser window opened on the site.
Because a new session is starting, the web server will assume you aren't logged in at all. Which, technically, you aren't.
I have the following scenario, and I wanted suggestions on what is the best way to handle this. My web app (ASP.NET 2.0 / IIS 6) generates PDF files, and I have a results page with links to those PDFs.
Now, I noticed that if I visit the results page, click on a PDF file (it opens in a new window), then re-generate the PDF file, and click on the same link in the results page, the OLD PDF is shown, instead of the new one. I had to delete the temporary internet files in order to see the new one.
So, since I'm NOT serving an ASPX that actually writes the PDF (and I do not want the Save dialog to show), but straight linking to the PDF file, I want to know what the best way to make sure the user always sees the latest file in the server, not a cached version.
I'm guessing adding no-cache headers is out of the question. But the PDF request would still go through an HTTP handler, so I'd like to know if I should create a specific HTTP handler to intercept requests for PDFs, or if i should do this at the IIS level...however I dont necessarily want to avoid caching ALL PDF's on that site.
Any suggestions? Thanks in advance for the help.
If your link to the pdf document had a unique querystring appended I believe that would prevent caching. Time in ticks is a good one to use, eg:
string.Format("{0}?t={1}", pdfFileUrl, DateTime.Now.Ticks);
I just had a similar issue. I have my page allows users to input data and generate new a pdf file Save clicked. The new pdf file overwrites the old one. In IE8, when user click the pdf link after the Save, the old pdf will always showed (user need to clear the cache to display the new one).
After hours of searching, I found that in IIS6, go to 'Output Caching', add a new cache rule with file extension '.aspx', tick both 'User-mode caching' and 'Kernel-mode caching' then under both options, select 'Prevent all caching'. This is working for me!
The fact the clearing your temporary internet files gave you the new version shows the browser is the source of the cache. You could turn iis caching off but that wouldn't stop proxies caching the document. If you need to be 100% sure that the user sees that latest version, I suggest using a query string value to cause the url to be different. The query string could be the pdf generation timestamp.
I have a web application which consists of many aspx pages ... one of them shows a grid with rows that can be exported to a file via button click. This works fine. Now I want to have that feature which allows a user to access an external link to this page (or another) and to export to a file and download. I dont need any information on the page, just the file download. How could I do this also including security features like encryption?
Thanks :)
The easiest way to do this is simply implement an HttpHandler that contains the logic to create that file and write it to the Response stream.
There are lots of examples of how to do this on the web that I won't repeat in this question. Just do a Google search for "Download File HttpHandler" and you should be golden.
One of the search results: http://www.c-sharpcorner.com/UploadFile/jhblankenship/DownloadingFromMemStreamHttp11262005061852AM/DownloadingFromMemStreamHttp.aspx
What you're going to have to do is when the gridview shows the correct rows to provide a 'unique link' which will be your website URL with url variables at the end. When the page loads it can check these variables and then use the database to look up the correct data etc.
Encryption in transit will be done via HTTPS (SSL), and to secure otherwise you would require a login to view the gridview / file.
I do not really understand how Google Code handles file versioning.
I am building a jQuery plugin that anyone can access. Like so:
<script type="text/javascript" src="http://jquery-old-browser-warning.googlecode.com/files/jquery.browser-warning.js"></script>
This script accesses other files on the same project (via ajax).
The problem is, that when I upload a new file, it just seems like there aren't any changed to it. Google recommends that new files should have new names.
But then I would have to change the filenames that the script loads.
But then I would have to change the script file as well, and that would break everybodys implementation (with the script-tag above)
Is there a way to force a file to change when uploading with the same filename?
PS: If I go directly to the project page's file list. Then I do get the file with the updated content. But as I said, not when getting it through ajax.
The cheapest trick in the book to prevent caching is adding some random content to a GET parameter:
www.example.com/resources/resource.js?random=1234567
You can for example use the current timestamp for this.
This, however, causes any and every access to re-fetch the content, and invalidates any client-side caching mechanism as well. I would use this only as a last resort. If Google are that stringent about caching, I'd rather develop a workflow that allows for easy renaming of files.
I don't know your workflow, but maybe you can work with versioned directories?
Like so:
www.example.com/50/resources/resource.js
www.example.com/51/resources/resource.js
that would keep whatever caching the client employs intact, but whenever there's a change from your end, the browser would reload the content.
I think Its just a cache on the browsers, So when you request file from ajax, just add random parameters or version number.
For example, Stackoverflow add version parameter to static contents like
http://sstatic.net/so/all.css?v=6638
Are you talking about uploading files to the "Downloads" area? Those should have distinct filenames, for example they should be versioned. If you're uploading the script code, that should be submitted by the version control system you're using, and should most definitely keep the same name across revisions.
Edit: your code snippet didn't show up on my page, misunderstood what you're trying. Don't imagine Google would be happy with you referencing the SVN repository every time some client page is loaded :)
We have created a web application, using ASP.NET, that allows users to upload documents and attach them to business entities, like customers, contacts and so on.
The application runs on the intranet and all files are uploaded through the web application into a shared folder on the server.
I would like, right from the web page, for the user to open the actual file, edit it and then save the changes back to the original location. This is a piece of cake in a Windows environment, I'm just wondering what, if any, is the best way to handle this in a web environment?
The files are usually Word documents, Excel documents and images.
Clarification
We would display all the attachments in a list format. We would like it so that the user would click on an edit link and the file would be opened in the appropriate application, for example, Microsoft Word or Microsoft Excel. I think the file associations in Windows would already handle this. We are just trying to save our user the time to download the original file, make their changes, delete the old file, and the upload the new file.
SharePoint does this by exposing FrontPage extensions which Word and Excel know how to deal with.
If you want to look at a commercial product for ASP.NET that allows you to edit images with AJAX (no need for installed software), I work for a company that has one (Atalasoft)
WebDAV is probably what you want. (Free)
If all your client computers are Windows, map a shared folder on the server to the same drive letter on every client and use the file:// format.
Let's say you share \ServerName\ShareName to H: on every client's computer, the you can make the link as file://h:\pat_to_the_file_under_your_share\fileName.doc
If not every one of the client's computers are in Windows, then you might try to make your links as follows (not sure if ot works):
file://\ServerName\ShareName\pat_to_the_file_under_your_share\fileName.doc
I'm trying to do something with using file:// instead of http:// but it's real sporadic based on the browser. Seems to work fine in IE, okay in Firefox, and goes nowhere in Chrome.
Looks like I may just be stuck with downloading, editing, and re-uploading the document.
It sounds like you want something similar t eRoom, where the browser works in conjunction with a component that intercepts a stream from http, stores it in a temp folder, then fires up Word or Excel and allows you to edit the stream.
You may have to create a component that will intervene and create a temporary local copy of the file.
This tool should do what you need.
http://www.dlitools.com/dlitools/dlitoolsHome.nsf/0FA6B8B31F831F468525736B0001C606/4BBD7E8684EA8DB78525754E006C63A3?OpenDocument