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ReadAllBytesAsync(path) path always combined with the contentrootpath

I want to return a files from virtual path directory, currently this is my code in C# asp net core.
var path = GetConfig.AppSetting["VirtualDirectoryPath:PathLocal"] + "/" +
_.data.Downloadpath;
var provider = new FileExtensionContentTypeProvider();
if (!provider.TryGetContentType(path, out var contentType))
{
contentType = "application/octet-stream";
}
var bytes = await System.IO.File.ReadAllBytesAsync("http://website.com/foldername/foldername/filename.pdf");
return File(bytes, contentType, Path.GetFileName(path));
the DownloadPath contains 'foldername/filename.pdf', and the virtual directory path contains the localhost domain, i tried to hardcode the path but it keeps returning "D://folder/folder/http://website.com/foldername/foldername/filename.pdf". I don't know why the url combined with the contentrootpath, can someone help me?
Actually, i also want to retrieve a virtual directory path as url from the virtual directory that i already created in the iis so that i can download the files from the url. I don't know how to code better, if you can help me with this too i'd very much appreciate it. TIA.

Ultimately, the problem is that you seem to believe File.ReadAllBytesAsync downloads files from the web, it does not. It only reads files on your local file system.
And because http:// files aren't supported, they're not considered to be rooted, and so it gets concatenated to the "current folder" and you get what you see.
Also never concatenate paths like that, that's what Path.Combine is for.

Xamarin media plugin get android image path

I am using the media plugin for xamarin forms (by james montemagno) and the actual taking of the picture and storing it works fine, I have debugged the creation of the image on the emulator and it is stored in
/storage/emulated/0/Android/data/{APPNAME}.Android/files/Pictures/{DIRECTORYNAME}/{IMAGENAME}
however in my app it will get a list of file names from an API I want to check if the image exists in that folder.
The following works fine on IOS
var documentsDirectory = Environment.GetFolderPath(Environment.SpecialFolder.Personal);
string jpgFilename = System.IO.Path.Combine(documentsDirectory, App.IMAGE_FOLDER_NAME);
jpgFilename = System.IO.Path.Combine(jpgFilename, name);
I have tried the 2 following methods for getting it on android but both are incorrect
var documentsDirectory = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal);
string jpgFilename = System.IO.Path.Combine(documentsDirectory, App.IMAGE_FOLDER_NAME);
jpgFilename = System.IO.Path.Combine(jpgFilename, name);
Java.IO.File dir = Android.OS.Environment.GetExternalStoragePublicDirectory(Android.OS.Environment.DataDirectory + "/" + App.IMAGE_FOLDER_NAME + "/" + name);
dir ends up as
/storage/emulated/0/data/{DIRECTORY}/{IMAGENAME}
jpgFileName ends up as /data/data/{APPNAME}.Android/files/{DIRECTORYNAME}/{IMAGENAME}
I dont want to hardcode anything in the paths but neither of these are right. I could not find anything in the GIT documentation for getting the file path except by looking at the path of the file created when taking a picture

The problem
I had the same kind of issue with Xamarin Media Plugin. For me, the problem is:
we don't really know where the plugin save the picture on android.
After reading all documentation I found, I just noted this:
... When your user takes a photo it will still store temporary data, but also if needed make a copy to the public gallery (based on platform). In the MediaFile you will now see a AlbumPath that you can query as well.
(from: Github plugin page)
so you can save your photo to your phone gallery (it will be public) but the path is known.
and we don't know what means "store the temporary data".
Solution
After investigating on how/where an app can store data, I found where the plugin stores photos on Android >> so I can generate back the full file names
In your Android app, the base path you are looking for is:
var basePath = Android.App.Application.Context.GetExternalFilesDir(null).AbsolutePath
It references your app's external private folder. It looks like that:
/storage/emulated/0/Android/data/com.mycompany.myapp/files
So finally to get your full file's path:
var fullPath = basePath + {DIRECTORYNAME} + {FILENAME};
I suggest you to make a dependency service, for instance 'ILocalFileService', that will expose this 'base path' property.
Please let me know if it works for you !

I resolved a similar problem. I wanted to collect all files for my app in a folder visible to all users.
var documentsDirectory = Android.OS.Environment.GetExternalStoragePublicDirectory(
Android.OS.Environment.DirectoryDocuments);
If you want to create Directory, add to your class using System.IO; and you have the same functions in a normal .NET application.
if (!Directory.Exists(path))
Directory.CreateDirectory(path);
If you want to create files or directory, you can use PCLStorage.
public async Task<bool> CreateFileAsync(string name, string context)
{
// get hold of the file system
IFolder folder = FileSystem.Current.LocalStorage;
// create a file, overwriting any existing file
IFile file = await folder.CreateFileAsync(name,
CreationCollisionOption.ReplaceExisting);
// populate the file with some text
await file.WriteAllTextAsync(context);
return true;
}

to get the private path
var privatePath = file.Path;
to get the public Album path
var publicAlbumPath = file.AlbumPath;
se the documentation here https://github.com/jamesmontemagno/MediaPlugin

Converting physical path to relative one in respect of http://localhost:

I use asp.net 4 and c#.
I have this code that allow me to find the physical path for an image.
As you can see I get my machine physical pagh file:///C:.
string pathRaw = HttpContext.Current.Request.PhysicalApplicationPath + "Statics\\Cms\\Front-End\\Images\\Raw\\";
Result:
file:///C:/......../f005aba1-e286-4d9e-b9db-e6239f636e63.jpg
But I need display this image at the Front end of my web application so I would need a result like this:
http://localhost:1108/Statics/Cms/Front-End/Images/Raw/f005aba1-e286-4d9e-b9db-e6239f636e63.jpg
How to do it?
PS: I need to convert the result of variable pathRaw.
Hope I was able to express myself unfortunately I'm not sure about terminology in this case.
Thanks for your help!

The easiest thing to do is get rid of the physical application path.
If you cannot do that in your code, just strip it off the pathRaw variable. Like this:
public string GetVirtualPath( string physicalPath )
{
if ( !physicalPath.StartsWith( HttpContext.Current.Request.PhysicalApplicationPath ) )
{
throw new InvalidOperationException( "Physical path is not within the application root" );
}
return "~/" + physicalPath.Substring( HttpContext.Current.Request.PhysicalApplicationPath.Length )
.Replace( "\\", "/" );
}
The code first checks to see if the path is within the application root. If not, there's no way to figure out a url for the file so an exception is thrown.
The virtual path is constructed by stripping off the physical application path, convert all back-slashes to slashes and prefixing the path with "~/" to indicate it should be interpreted as relative to the application root.
After that you can convert the virtual path to a relative path for output to a browser using ResolveClientUrl(virtualPath).

Get the root of your application using Request.ApplicationPath
then use the answer from this question to get a relative path.
It might need a bit of tweaking but it should allow you to do what you're after.

Left-strip your pathRaw content by the Request.ApplicationPath and construct the url using
Uri navigateUri = new Uri(System.Web.HttpContext.Current.Request.Url, relativeDocumentPath);

Make use of
ApplicationPath - Gets the ASP.NET application's virtual application root path on the server.
Label1.Text = Request.ApplicationPath;
Image1.ImageUrl = Request.ApplicationPath + "/images/Image1.gif";

You can use Server.MapPath for this.
string pathRaw = System.Web.HttpContext.Current.Server.MapPath(“somefile.jpg“);

Problem with relative path in System.file.io of asp.net

I'm storing the file path in the database as ~/FolderName/FileName and when i try to open the file using System.IO.FileInfo(filePath) in this manner. It is not able to decipher the file path. Moreover i'm using this statement in a class DownloadFile, so i'm not able to use Page.Server.MapPath. Is there a work around for this problem.
These are the following lines of code that i'm using:
if (dr1.Read())
{
String filePath = dr1[0].ToString();
HttpContext.Current.Response.ContentType = "APPLICATION/OCTET-STREAM";
String disHeader = "Attachment; Filename=\"" + fileName + "\"";
HttpContext.Current.Response.AppendHeader("Content-Disposition", disHeader);
System.IO.FileInfo fileToDownload = new System.IO.FileInfo(filePath);
string fullName = fileToDownload.FullName;
HttpContext.Current.Response.Flush();
HttpContext.Current.Response.WriteFile(fileToDownload.FullName);
sqlCon.Close();
}
where the filepath is of the format ~/ComponentFolderForDownloading/FileName.exe
How can i solve this problem?

If you can't use Server.MapPath for determining the file location, you need to use something else. The FileInfo class can not take an ASP.NET virtual path in its constructor. It needs the real, physical path of the file.
You'll need to strip the ~/ from the front of the path; perhaps exchange the / for a \, and then use Path.Combine with the root directory of your application to find the physical location. But that assumes that your locations are in physical directories - not virtual ones.
Server.MapPath was, of course, made specifically to do this.
An alternative would be to store the real, physical locations of the files in the DB; either in addition to or in stead of the virtual, ASP.NET ones.

If you know you are running in IIS, you can use:
HttpContext.Current.Server.MapPath("~/someurl");

File.Exists using the wrong root path?

In my c# class I wrote I have a photo property that returns the photo source if the image exists (nothing or default image otherwise). In my code I use:
public string Photo
{
get
{
string source = "~/images/recipes/" + id + ".jpg";
if (File.Exists(source))
return "~/images/recipes/" + id + ".jpg";
else
return "";
}
}
If I get the FileInfo() information for this image I see that I tries to find this image in the following directory: C:\Program Files (x86)\Common Files\Microsoft Shared\DevServer\10.0\~\images\recipes
Of course the image is not located in that directory and File.Exists is returning me the wrong value. But how can I fix this?

Try this:
if(File.Exists(System.Web.HttpContext.Current.Server.MapPath(source)))

You need to map the relative path back to a physical path:
string source = HttpContext.Current.Server.MapPath("~/images/recipes/" + id + ".jpg");

You'll have to use:
Server.MapPath(source)
As you can not be 100% sure where the code will be running from, ie. it will be different in development and on a production server. Also are you sure ~/ works in windows? Wont that just be interpreted as a directory named ~? Unless thats what you want.