Develop Reference

c# - Physical path given, virtual path expected in Server.MapPath

I trying to change my directory which in my local c disk, but where errors says in the title. Is there any way aside from using Server.MapPath?. I'm using a ZipOutputStream nuget package.
I want to locate my directory in C: instead inside the project folder.
public FileResult DownloadZipFileSig(string FileId){
var fileName = "FilesDL".zip";
var tempOutPutPath = Server.MapPath(Url.Content("C:/Users/SDILAP2/Desktop/ID_Esig_Files")) + fileName;
using (ZipOutputStream s = new ZipOutputStream(System.IO.File.Create(tempOutPutPath)))
{
s.SetLevel(9);
byte[] buffer = new byte[4096];
List<string> stringList = FileId.Split(',').ToList();
List<string> tempList = new List<string>();
foreach (string str in stringList)
{
if (System.IO.File.Exists(Server.MapPath("C:/Users/SDILAP2/Desktop/ID_Esig_Files/" + str + ".jpeg")))
{
tempList.Add(Server.MapPath("C:/Users/SDILAP2/Desktop/ID_Esig_Files/" + str + ".jpeg"));
}
}
stringList = tempList;
for (int i = 0; i < stringList.Count; i++)
{
ZipEntry entry = new ZipEntry(Path.GetFileName(stringList[i]));
entry.DateTime = DateTime.Now;
entry.IsUnicodeText = true;
s.PutNextEntry(entry);
using (FileStream fs = System.IO.File.OpenRead(stringList[i]))
{
int sourceBytes;
do
{
sourceBytes = fs.Read(buffer, 0, buffer.Length);
s.Write(buffer, 0, sourceBytes);
} while (sourceBytes > 0);
}
}
s.Finish();
s.Flush();
s.Close();
}
return File(finalResult, "application/zip", fileName);
}

You might be not quite grasping how web URL's work, and how server.mappath() is to be used.
Web users:
When you have a web based url, then all html markup in a page, or even user supplied URL's are so called web based.
So, if you have a folder from the root of your web site say called MyUpLoads
Then that is just a folder in the web site path names.
eg:
www.mywebsite/UpLoadFiles/cat.jpg
And if you write html markup, then you can and could provide a URL to the above picute, or say with a html image control, you could set the ImageURL or "source" (src) to that file.
And if you using IIS (and not IIS express), then of course you can add what is called a virutal folder. Say some big server drive on ANOHTER computer on the same network.
So, that virtual folder could be anywhere on your network, and of course AGAIN for web HTML, or web URL's, again you use this format:
www.mysite/MassiveFolder/info.pdf
or maybe
localhost:5403/MyUpLoads/cat.jpg
However, in code behind?
ANY code behind (c# or vb.net) ALWAYS uses plane jane WINDOWS file paths.
These are valid full windows file names.
That means that code behind is 100% free to open/read/use/see/play with ANY file on the computer, and any file even on the computer network.
So when you use
server.mapPath("localhost:5403/MyUpLoads/cat.jpg")
Then the above is translated into a local plane jane DOS/WINDOWS file path!!!!
The above may well become
C:\Users\AlbertKallal\source\repos\CSharpWebApp\MyUpLoads\cat.jpg
So keep in mind:
web urls - HTML/asp markup in a page = web based syntax/path.
computer path: plane jane full path names like all windows software.
So, in your case?
var fileName = "FilesDL".zip";
var tempOutPutPath = #"C:/Users/SDILAP2/Desktop/ID_Esig_Files")) + fileName;
So you don't need nor want to user server.mappath, since that is ONLY for a given HTML or web based URL that you want to translate into the local computer file path system.
Since your path name(s) are already in that format, then no need is required.
in fact, keep in mind that you can use this fact to your advantage.
ANY folder (or a vitural folder) will appear in your valid URL's and path names (web based).
However, you might have some pdf's, or sensitive documents. So move that folder OUT of the root or web project folders.
Now, no valid URL's exist, or are even allowed.
However, code behind? It can run, see and use ANY file on your computer - and you use code behind to get those files - but the web site, web side of things has NO ability to use or see or get those files. And you can still do things like say provide a download button, but your code behind can fetch the file, read it and pump it out to the end user (stream the file).
So you only need (have) to use the Server.MapPath function WHEN the URL comes from the web site or html markup. This will translate that web based URL into a regular good old fashion full qualified windows file path name.
However, if you already have that full windows path name, then no URL translate to windows file path is required.
So, for the most part, your code behind can look at, see, grab and play with files on the server. Web users, or web based urls MUST be part of the folders in the web site, but no such restrictions exist for the code behind.
Now, when the code is deployed to a web server, often some file security rights on in place, but as a general rule, that web code behind is NOT limited nor restricted to JUST folders in the web site. Those valued URL's are a restriction for the users and web browsers, and as noted, often a folder outside of the web site is used for security purposes, since no possible valid web based paths can use/see or even resolve to file outside of the root starting folder of the web site.
So for those existing files, you don't need server.mappath.

Why can't I access static files that I add programmatically from a POST request?

I'm attempting to make a basic .NET API for managing a collection of media (images and videos).
I have configured the webroot to be a folder called "site", and within that folder is a folder called "media" where these files are stored. I can access a test media file that is saved in /site/media/Smush.jpg by loading https://localhost:5001/site/media/smush.jpg - this serves the image as expected.
I have created a method that receives a POST request containing form data from my frontend, and this method saves the file to the webroot using a filestream, code below:
[HttpPost]
[Route("/media/add")]
public async Task<HttpResponseMessage> MediaAdd()
{
try
{
//get the form
var form = HttpContext.Request.Form;
//if there's a route, add it into the filepath, otherwise leave it out and have the filepath go straight to media (this prevents an exception if route is blank)
string filePath = form["route"] == "" ? Path.Combine(_hostingEnvironment.WebRootPath, "media") : Path.Combine(_hostingEnvironment.WebRootPath, "media", form["route"]);
//get the first (should be only) image - DO WE WANT TO BE ABLE TO ADD MULTIPLE IMAGES? PROBABLY TBH
IFormFile image = form.Files.First();
if (image.Length > 0)
{
//check the directory exists - create it if not
if (!Directory.Exists(filePath)) {
Directory.CreateDirectory(filePath);
}
using (Stream fileStream = new FileStream(Path.Combine(filePath, form["filename"]), FileMode.Create))
{
await image.CopyToAsync(fileStream);
return new HttpResponseMessage(HttpStatusCode.OK);
}
}
else {
return new HttpResponseMessage(HttpStatusCode.BadRequest);
}
}
catch (Exception e)
{
return new HttpResponseMessage(HttpStatusCode.BadRequest);
}
}
My frontend submits a route, filename and the media file, and this is used to save the image. This all works fine; I can submit an image with the path "test" and the name "test.jpg", and the API correctly stores the file at /site/media/test/test.jpg. I can view the file in the solution and see a preview of the image, as with Smush.jpg.
However, attempting to load https://localhost:5001/site/media/test/test.jpg results in a 404. Why is this the case? Can I not add files into the webroot through code and have them be accessible as static files as if I added them to the solution in my IDE? Are there any alternative ways of handling this?
I am using .NET 5.0, and have
app.UseStaticFiles(); in Configure() in Startup.cs.
Sorry if this is a duplicate, but I couldn't find anything else like this.
EDIT:
On checking things again, it seems like rather than my files being at https://localhost:5001/site/media, they are simply in https://localhost:5001/media. I am not sure how I was able to access Smush.jpg at https://localhost:5001/site/media/Smush.jpg before.
It seems as though the webroot is not included as part of a URL to access files within it.
As it is now, I have got what I was looking for it to do.

Well first a security concern as also #Heinzi pointed out...
string filePath = form["route"] == "" ? Path.Combine(_hostingEnvironment.WebRootPath, "media") : Path.Combine(_hostingEnvironment.WebRootPath, "media", form["route"]);
What if the user sends form.route == "../../" and instead of image he updates the appsettings.json file ?
Check this out and have that in mind if you're planing to release this code to a production environment and make sure you only accept image files.
On the other hand if you are serving static files from a folder different to wwwroot please use this configuration

Why the 404
It makes sense. You are under the controller/action paths. Going under the site url the engine does the following:
When you request https://localhost:5001/site/media/test/test.jpg the code tries to find the media controller and the test action. It is not looking for static files on the filesystem. Since there is no such controller/action pairs, it will not find anything and thus return 404 not found.
If you saved the files in https://localhost:5001/static/media/test.jpg outside of the mapped routes, you would be able to access it.
Look inside your code for:
MapHttpRoute
Which is used to configure how to identify controller actions which are not decorated with the [Route] attribute.
Security concern
When you want to upload a file, you should consider a better solution and not one that accesses directly your filesystem.
Possible options:
Blob storage on the cloud
Database blobs
Don't forget to sanitize the input with an antivirs or some similar solution.

Downloading images from publicly shared folder on Dropbox

I received a link to shared folder from e-commerce company. The link is public and not shared with my dropbox account directly.
How do I get an url to the image that I can pass to either DownloadAsync method of the same sdk or simply HttpClient and well ... download it?
Ideally it would be the same link I get when I click on the image when viewing that shared folder in a browser.
https://www.dropbox.com/sh/{folder_hash}/{file_hash_maybe}/{filename}?dl=0
This is what I have tried:
using Dropbox.Api;
using Dropbox.Api.Files;
...
var accessToken = "abracadabra";
var sharedFolderUrl = "https://www.dropbox.com/sh/{folder_hash}?dl=0";
using (var dbx = new DropboxClient(accessToken))
{
var sharedLink = new SharedLink(sharedFolderUrl);
var sharedFiles = await dbx.Files.ListFolderAsync(path: "", sharedLink: sharedLink);
// sharedFiles - has over 13,000 entries, I use cursor to get them all.
foreach (var file in sharedFiles.Entries)
{
if (file.IsFile)
{
// tried this, but:
// 1. it's crazy to loop through all
// 2. link.Response.Url gives me the same url to a shared folder for all items
var link = await dbx.Sharing.GetSharedLinkFileAsync(url: sharedFolderUrl, path: "/" + file.Name);
}
}
}

Using the GetSharedLinkFileAsync method is the right way to programmatically download a file from a shared link. It actually gives both the metadata (in the link.Response in your code like you mentioned), as well as the file data directly (not via a URL).
To access the file data, you can use any of the GetContentAs... methods documented under IDownloadResponse as returned by GetSharedLinkFileAsync. In your code, that would look something like: link.GetContentAsStreamAsync() (or whichever one you want).
Alternatively, if you want to download the entire folder from the shared link, you can use the URL parameters documented in this help center article. (That may fail for very large folders though.)

Multiple upload files from file list in User computer to server in ASP.Net

pe someone can help me on this.
I've been googling & searching a lot regarding this issue.
I'm working on web application where I need to :
Click a button to get a folder/directory of files - Done with
javascript
Get list of available files is the selected folder/directory - Done
with javascript
Start uploading those file in the list into server folder - Failed!
As I understand my limitation so far :
I cannot programmatically assign a value to asp:FileUpload control -
readOnly
I cannot access those file in the list in FileInfo/FileStream - it's fail as it can't find the source file given from the list due to it's not
came from server directory
came from server directory
I cannot simply try to use File.Copy to upload the file - it's fail as it can't find the source file given from the list due to it's not
came from server directory
I've been getting error :
"Could not find a part of the path"
List of files in the folder, example :
File1.pdf
File2.png
File3.txt
File4.xls
File5.jpg
While in the server, I already create a folder named as "Temp" but the problem actually because system can't recognize the path of those file in the list.
This is part of my code :
string strPath = #"C:\Users\Administrator\Desktop\Sample";
string strListedFiles = txtList.InnerText.ToString();
string[] strFiles = strListedFiles.split(new Char[] { '\n' }, StringSplitOptions.RemoveEmptyEntries);
foreach(string strFile in strFiles)
{
FileInfo fiFile = new FileInfo(strPath.ToString() + "\\" + strFile.Trim());
FileStream fsFile = fiFile.OpenRead(); //Failed at here
...
...
...
...
}

Perhaps you are looking for something which has been shown with demo in this tutorial.
This will allow you to upload multiple files concurrently.
Another alternative example with jQuery MultiFile is given here.

Visual Studio 2010 working directory

I'm developing a C# asp.net web application. I'm basically done with it, but I have this little problem. I want to save xml files to the "Users" folder within my project, but if I don't psychically hard code the path "C:......\Users" in my project it wants to save the file in this "C:\Program Files (x86)\Common Files\microsoft shared\DevServer\10.0\Users" folder, this is an annoying problem because I can't use the hard coded directory on our web hosts server. Also, I have a checkbox list that populates from the the "DownloadLibrary" folder in my project, and its suppose to download the files from that fold but its also looking to the "C:\Program Files (x86)\Common Files\microsoft shared\DevServer\10.0\" folder for download even though its populating from the correct folder. I'm very confused by this, its the first time something like this has ever happened to me. Can anyone please help me with this, its the only thing standing in my way to complete this project.

You don't want to use the working directory at all; you want to use a directory relative to where the web application is located (which can be retrieved from HttpRequest.ApplicationPath.
HttpRequest request = HttpContext.Current.Request;
// get the physical path to the web application
string pathToApp = request.MapPath(request.ApplicationPath);
string usersPath = System.IO.Path.Combine(pathToApp, "Users");
Update
As VincayC points out; asp.net development is not my strongest skill ;) The above code is essentially equivalent of this (much simpler) code:
string usersPath = HttpRequest.Current.Request.MapPath("~/Users");
If this code appears in the code-behind of a page, you can probably cut HttpContext.Current as well, since the page has a Request property.

That did fix the one problem I'm having, but the downloads are still not downloading from the right place, the program still wants to get the files from "C:\Program Files (x86)\Common Files\microsoft shared\DevServer\10.0\" directory here is the code I'm using
--Code to populate the checkbox--
HttpRequest request = HttpContext.Current.Request;
// get the physical path to the web application
string appPath = request.MapPath(request.ApplicationPath);
string directory = System.IO.Path.Combine(appPath, "DownloadLibrary/");
// Get the list of files into the CheckBoxList
var dirInfo = new DirectoryInfo(directory);
cblFiles.DataSource = dirInfo.GetFiles();
cblFiles.DataBind();
--Download Button Code--
// Tell the browser we're sending a ZIP file!
var downloadFileName = string.Format("Items-{0}.zip", DateTime.Now.ToString("yyyy-MM-dd-HH_mm_ss"));
Response.ContentType = "application/zip";
Response.AddHeader("Content-Disposition", "filename=" + downloadFileName);
// Zip the contents of the selected files
using (var zip = new ZipFile())
{
// Add the password protection, if specified
/*if (!string.IsNullOrEmpty(txtZIPPassword.Text))
{
zip.Password = txtZIPPassword.Text;
// 'This encryption is weak! Please see http://cheeso.members.winisp.net/DotNetZipHelp/html/24077057-63cb-ac7e-6be5-697fe9ce37d6.htm for more details
zip.Encryption = EncryptionAlgorithm.WinZipAes128;
}*/
// Construct the contents of the README.txt file that will be included in this ZIP
var readMeMessage = string.Format("Your ZIP file {0} contains the following files:{1}{1}", downloadFileName, Environment.NewLine);
// Add the checked files to the ZIP
foreach (ListItem li in cblFiles.Items)
if (li.Selected)
{
// Record the file that was included in readMeMessage
readMeMessage += string.Concat("\t* ", li.Text, Environment.NewLine);
// Now add the file to the ZIP (use a value of "" as the second parameter to put the files in the "root" folder)
zip.AddFile(li.Value, "Your Files");
}
// Add the README.txt file to the ZIP
//zip.AddEntry("README.txt", readMeMessage, Encoding.ASCII);
// Send the contents of the ZIP back to the output stream
zip.Save(Response.OutputStream);</pre></code>
I'm not sure how to get the downloads to point to my application directory,I tried everything I can think off.