I'm using ASP.NET with MVC 2 and have trouble translating a local file url to a server address. It would seem like a fairly simple and common task, but google searches gives me no good answers. (Perhaps i suck at searching)
I have a controller that takes a file from a html form in a view and saves it to disk. I need to return the real url of this file back to the View. Whatever method i use, I always get a string with the local path of the file instead of the http path.
I suspect the url might get translated to http address once the project has been deployed, but I really need the server address when debugging without having to hardcode anything.
Consider the following example in some controller method:
string url = Url.RequestContext.HttpContext.Server.MapPath("~/Content/Files/" + Path.GetFileName(file.FileName));
// outputs: "C:\\Users\\xxx\\Documents\\Visual Studio 2010\\Projects\\[ProjectName]\\Content\\Files\\file.png"
// whereas i'd like something like "http://localhost/Content/Files/file.png" instead
any ideas?
It depends on where you are storing this file. If you are storing it in a directory which is outside of the virtual directory root you won't be able to access it. If the file is inside a folder which is accessible over HTTP you could simply use the Content method:
string url = Url.Content("~/Content/Files/foo.txt");
Related
While I'm sure the title could be improved for clarity, my meaning is thus:
When fetching a URL for a file download at http://example.com/dir1/dir2/file.zip, the response code is 200, yet attempting to access http://example.com/dir1, or http://example.com/dir1/dir2, elicits a 404 response code.
Why is this?
URLs don't necessarily correspond to actual directories on the server. Ultimately the path component of a URL is just a name; the server can translate that name to whatever it wants on the back end.
In this case it seems likely that /dir1/dir2/ is a directory on the server, but even so that doesn't mean anything. The server knows about a resource named /dir1/dir2/file.zip, but doesn't know anything about a resource named /dir1.
From https://en.wikipedia.org/wiki/Query_string
A web server can handle a Hypertext Transfer Protocol request either
by reading a file from its file system based on the URL path or by
handling the request using logic that is specific to the type of
resource. In cases where special logic is invoked, the query string
will be available to that logic for use in its processing, along with
the path component of the URL.
What does the quote mean by the two methods by which a web server can handle a HTTP request
"by reading a file from its file system based on the URL path"
"by handling the request using logic that is specific to the type of resource"?
Can you give specific examples to explain the two methods?
Is the query string used in both method?
Thanks.
by reading a file from its file system based on the URL path
^ The web site uses a generic mapping mechanism to convert a URL path to a local filesystem path, and then returns the file located at that path. This is common with static files like .css.
by handling the request using logic that is specific to the type of resource"
^ The web site turns control over to a web application, which contains code written by a developer. The code reads the query string and decides what to do. The logic for deciding what to do is completely customizable, and there does not need to be a static file in the local filesystem that matches the URL.
Is there a way to get the server url (ex: http://www.myapp.com:8080/applicationFolder) without having access to a Request object ?
I need the url at aplication_start and in some classes where the Request object with all the goodies is not available.
note: I know that getting the application folder can be done using
VirtualPathUtility.ToAbsolute("~/");
HttpContext.Current.Request is a static property that always returns the Request object currently executing for the session.
I think all you need a custom solution to know when first request is made after application starts, and then you can send any email you want.. this is the similar problem with solution here http://weblogs.asp.net/reganschroder/archive/2008/07/25/iis7-integrated-mode-request-is-not-available-in-this-context-exception-in-application-start.aspx this do first initialization check in BeginRequest event.
There can be many different addresses all pointing to the same ASP.NET website, like using IP address or name. There might be more than 1 DNS name pointing to the same ASP.NET application. Therefore, HttpApplication, the parent class of Global, does not know which URL a visitor will use. Even IIS doesn't know. Therefore, you have to wait for the first request and then check in the request what URL the visitor uses to access your site. Something like this:
string baseUrl = Context.Request.Url.GetLeftPart(UriPartial.Authority);
One has to use Context to get access to the Request during Global.Application_Start, because Global.Request is not initialised yet.
I have a json file on my server.
http://myserver/myfile.json
If I type the url into a browser I get a page not found error.
If I set the url of a http service to the path of the json file the httpservice wont load it.
Is it possible to load a json file in this way or does the json file have to be the result of a server page request eg: http://myserver/getjson.php
The problem is this:
If I type the URL into a browser I get a page not found error.
It sounds to me like you have a configuration issue on your web server.
There is no way a Flash App can load something from your server that the server itself cannot deliver.
There are two different ways to approach this. You may have to set a mimetype on the server so the file is recognized. Or you may have to define the 'json' extension as an allowable file.
How you go about doing either of those things depends on the web server.
Consider this scenario:
You want to redirect (REDIRECT) a user to a certain handler (aspx or ashx) without hardcoded path.
You have the name of the handler's class, you can even get it's type (ASP.whateverpageclass).
Now, how do you get the virtual path?
If I understood correctly, you want a virtual path for a handler if you have the name/type of implementing class. AFAIK, this is not possible because there need not be one to one correlation between two - from ASP.NET run-time perspective, it has to map a virtual path to some handler class (and not a vice-verse). For example, you can have all paths to certain extension be mapped with the same handler type.
As far as your main problem of avoiding hard-coding is concerned, you can handled that having configurable url (to redirect) or have persistent store (database, xml file or config file) that can map some key (for example, handler class name) to virtual path to redirect.