New opened window opens but closes immediately - c#

I'm trying to download file from FTP using javascript, for which I created the following topic:
Is it possible to download file from FTP using Javascript?
From there I learned that I can use window.open('ftp://xyz.org/file.zip'); to download the file. It opens a browser new window, but the window closes immediately.
How I can I force it to stay open?
Actually I do all these in Silverlight application:
Here is the code:
HtmlPage.Window.Eval("window.open('" + url+ "', 'Download', 'height=500,width=800,top=10,left=10');");
I also tried this,
string targetFeatures = "height=500,width=800,top=10,left=10";
HtmlPage.Window.Navigate(new Uri(url), "_blank", targetFeatures);
But both results in same : it opens a window, and closes it immediately. I see it just for fraction of second!

I know this doesn't answer your question, and I'm sure you know all of this. I'm answering more because I don't see this point brought up often. :)
Silverlight has very limited support for client interactions. Javascript is a shim that in my opinion gets overused to try and bypass things that Silverlight was architectured against. It would have been very easy for Microsoft to include FTP support in Silverlight but it was excluded for a reason.
However, Silverlight has great support for webservice interactions. So the recommended way of getting a file would be to call a webservice that would do the FTP transfer for you and then send the contents down to the Silverlight application via the webservice. Possibly even processing it on the webservice side for any business logic etc.
Like I said, I suspect your requirement is to not use a webservice (to pass the bandwith cost onto the user most likely). But it'd be interesting to know more about your business problem instead of your technical problem for the solution you've chosen.

It closes because it triggers file download. You can open two windows - one for message and one to download file, but I thiunk user will know it is downloading...

If I were you, I'd open up a page that has whatever visual/UI stuff you'd want to show the user, and either have a META tag that redirects to the download URL, or has a javascript blurb to fire off said download. That way, your window will stay open, but the download will still start automatically.

to keep it open use
var test = window.open();
test.location = 'ftp://openbsd.org.ar/pub/OpenBSD/2.0/arc/kernels/bsd.ecoff';
and to not open any window use
window.location = 'ftp://openbsd.org.ar/pub/OpenBSD/2.0/arc/kernels/bsd.ecoff';
or make a normal link

Remember that a browser is not meant to "display" (visually anyway) the FTP protocol, and not all browsers will suport it. If you want to allow the user to download something, consider using a normal http:// protocol, and opening a window normally as others have suggested.
If you really need the download to be hosted via FTP, consider your backend ingesting (and caching) the file and return it to the user via http

There is nothing to be parsed on the browser's side, hence it closes. If you want to have the page open, you'll have todo something dirty. Like creating a html (or php) page and serve the content you want the user to see, then with a hidden i-frame which will call the FTP contents.
This way your user will see the content you want them to see, and the file is being downloaded.

I had the exact same problem, Silverlight opening a new window for downloading a file would flash a blank window up briefly and it would disappear again without the file download occurring.
This seemed to happen in IE 8 (not 9 and up) and could be fixed by going into Tools->Internet Options->Security then click Custom level... (for whatever zone your site would be in) and go to Downloads->Automatic prompting for file downloads and make sure this is Enabled (I also have File download enabled below that). This Automatic prompting for file downloads setting seems to be absent from IE 9+.
Another workaround is to not open in a new window, if the target url immediately downloads a file it won't change the current window so there's no difference in UX:
HtmlPage.Window.Navigate(new Uri("\download.ashx?fileid=12345"));

Related

uploading a file from folder with out browse in asp.net

i just wanna upload afile from a fixed path, so i dont want browse button, I need just a TextBox(Path of my file some thing like c:/junk/upload) and and upload button.some thing like
[TextBox.Path][UploadButton]
or can i get the code in java applets or any other lanaguage?
For security reasons, a webpage loaded in a browser from internet cannot directly refer the local file system. You need a desktop application or plugin to achieve this.
no we can make using asp.net or java applets and yes what you said is right, security reasons! , but every applications has a sand box limits and thats include file handling as default , and we achived that. with out problem

asp.net check if a file from the Response.OutputStream has been saved/opened

I am building an excel file (using EPPLUS) on a web page which gives the option to either save or open the file.
Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
Response.AddHeader("content-disposition", "attachment; filename=Excel_List.xlsx");
package.SaveAs(Response.OutputStream);
Response.End();
That works fine. I just want to know how can I check if the user has either opened/saved the file?
Is there an event for that?
The simplest answer is you cannot. Once the server has handed the file off to the client ASP.NET has no control over it.
You could, in theory, place a macro in the Excel file to call a URL on your server, but that's assuming the user opens the Excel file and allows for the execution of the macro (which is disabled in modern Excel versions).
You cannot determine it. After the output is generated you have no info about download process or actions that user takes on downloaded file. It is caused mostly by web browser security limitations.
No, that is not what HTTP is for. If you can successfully send all data from the server, you may assume the client has received it all. Client may then discard, save, print, copy, do whatever they like with the data.
If you want to perform such a check, you should do it from the Excel file itself. But then again you shouldn't, because of privacy. If I ever caught an Excel file phoning home, I don't know what'll happen.
It isn't possible to know if they actually opened it in Excel without adding a macro to the file, but there are ways that you can send a confirmation to the server that the download was completed successfully. For this you would need to embed a rich client in the browser to handle the HTTP request rather than doing it with the browser alone. Something like SoftArtisans XFile can be used for this. Our .NET Excel library also comes with an ActiveX control that can manage the download process (called the OfficeWriter Assistant).
Disclaimer: I work for SoftArtisans

Better user experience for website in asp.net MVC

I have a page that downloads a large HTML file from another domain then serve it to the user. The file is around 100k - 10MB and usually takes about 5min. What was think about doing something like this to make the user experience better.
download file
if file is not download within 10 seconds then displays a page that tells the user that the file is being downloaded
if the server completes the download in 1 second then it will serve the downloaded html
can this be done? do I need to use the async feature?
Updated question: the downloaded file is a html file
In order to provide an 'asynchronous' file download try a trick that Google is using: Create a hidden iframe and set it's source to the file you want to download. You can then still run javascript on your original page while the file is being downloaded through the iframe.
I think you should:
Return an HTML page to the user straight away, to tell them the transfer has started.
Start the download from the other domain in a separate process on your server.
Have the HTML from step 1 repeatedly reload, so you can check if the download has completed already, and possibly give an ETA or update to the user.
Return a link to the user when the initial transfer is complete.
It sounds like you need to use a waiting page that refreshes itself every so often and displays the status of your download. The download can be run on a separate thread using a System.Threading.Task, for instance.

While downloading a file, all requests are blocked

I'm having an issue within my application Pelotonics. When a user downloads a file the system seems to block all incoming requests until that file is done downloading. What is the proper technique to to open a download dialog box (standard from the browser), let the user start downloading the file, then while the file is downloading, let the user continue throughout the application.
The way we're getting the file from the server is we have a separate ASPX page that get's passed in a value through the query string, then retrieves the stream of the file from the server, then I add the "content-disposition" header to the Response and then loop through the file's stream and read 2KB chunks out to the response.outputstream. Then once that's done I do a Response.End.
Watch this for a quick screencast on the issue:
http://www.screencast.com/users/PeloCast/folders/Jing/media/8bb4b1dd-ac66-4f84-a1a3-7fc64cd650c0
by the way, we're in ASP.NET and C#...
Thanks!!!
Daniel
I think ASP.NET allows one simultaneous page execution per session and I'm not aware of any way to configure this otherwise.
This is not a very pretty workaround, but it might help if you rewrote ASP.NET_SESSIONID value to the request cookie in Application_BeginRequest (in global.asax). Of course, you would need to the authentication some other way. I haven't tried this, though.
Another way would be launching a separate thread for the download process, but you would need to find a way how this can be done without the worker thread closing it's resources.
May I ask, is there a reason why don't you just use HttpResponse.TransmitFile?

How to launch a browser and later direct it to a page?

I need to launch a browser, do some work and then make the browser navigate to a URL (in that order).
The first part is of course simple and I have a Process object. I am at a loss as to how to later direct it to the target page?
How do I treat the Process as a browser and make it navigate to the desired page?
Any help, pointers, code snippets appreciated.
Instead of launching the browser & then navigating to the page, just tell the OS that you want to run the URL. Windows will pick the correct browser, and navigate the user to the given URL.
System.Diagnostics.Process.Start("http://www.StackOverflow.com");
If you don't need to do this in production, you could use a testing library such as WatiN to do this:
using WatiN.Core;
//Placeholder page to launch initial browser
IE ie = new IE("http://www.google.com");
DoSomeWork();
//Now navigate to the page you want
ie.GoTo("http://stackoverflow.com");
My first instinct for this question was DDE, but it appears that has been decommissioned in Windows Vista so that is no good. Shame, as it was the only consistent mechanism in Windows for Interprocess Communication (IPC)...oh how I miss Arexx on the Amiga.
Anyhow, I believe the following will work but unfortunately, due to the way it works, it launches Internet Explorer irrespective of the configured browser.
If your application has a Form, then create a WebBrowser control on it. Set this to non-visible as we are only making use of its as a launching device rather than to display the web page.
In code, at the point where you want to show a web page, use the following code:
webBrowser1.DocumentText = "window.open('How to launch a browser and later direct it to a page?', 'BananasAreOhSoYummy');";
What this does is to tell the WebBrowser control, which is just the IE in disguise, to open a new window called 'BananasAreOhSoYummy'. Because we have given the window a name, we can use that line repeatedly, with different URLs, to change the page in that particular browser window. (A new window will be opened if the user has happened to close it.)
I will have a think about an approach that honours the user's default browser choice.
If you don't need the actual instance of IE, you can use the System.Windows.Forms.WebBrowser control.
I think instead of sending the browser a url you could send it javascript that would run and direct the browser to a site.
Not sure if this would work but I see no reason why it wouldn't

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