i have a question, I have this code
foreach (string line in File.ReadLines(**#"C:\fis32v6\fis32.ini"**))
{
if (line.Contains("TEST1"))
{
Label1.Text="TEST1";
PdLine = "1";
}
}
DataSet ds;
ds = GetData(PdLine.ToString());
I want to read from txt file on client specific line with condition. When developing this and building the code it works, what ever i change in txt file can be read from my PC. But when I run the website on server it reads the txt file on that server instead of client I opened the website.
Is there any possibility to make the path relative?
As John mentioned that would be a huge security issue, mostly to make sure the website doesn't dig around in your system.
However it can be instigated from client side.
Just have search here on SO for 'upload file using asp.net' there are loads of hits with answers listed.
You didn't mention specific versions you use (MVC?, asp.net? / core?), and no context as to what workflow your code is running in (is it run on connection or during a specific process), is it configuration settings used for the web session itself? but it is possible to upload.
Should you require the file during startup that might be a bit trickier as you'd have to upload it somehow.
If however it is settings for the web session, why not save it in a cookie?
Related
I am developing an application in asp.net, vs2015 using c# and the development environment is a Win10Pro machine. I can use any of the various methods to obtain the working directory and see if a particular file exists on the dev pc, but not on the Web Server. I have tried the methods laid out on:
Get current application physical path within Application_Start
All work on the Dev PC, but when used on the Web Server it will not return the working directory. The Server is a 2016 Data server using IIS10. The issue is that the web site I am putting together work fine, except to display GrapeCity ActiveReports reports AR15. The web page containing their web viewer opens just fine and is looking for a report file (MyReport.rdlx). The global.aspx file is pointing to the root directory but when the web viewer opens up, it says File Not Found. I have absolutely no idea and tech support is not sure. Is this an IIS issue that is preventing the code to locate and verify the file is there? Any direction would be much appreciated. This has been very frustrating and time consuming.
AppDomain.CurrentDomain.BaseDirectory does not work, HttpRuntime.AppDomainAppPath does not as well as all the others. The request comes back blank.
string filename = AppDomain.CurrentDomain.BaseDirectory.ToString() +"SPU01_Dates.rdlx";
if (File.Exists(filename))
{
Response.Write("YES");
}
else
{
Response.Write("NO");
Response.Write("</br");
Response.Write(filename);
}
All this just returns nothing.
Thanks.
Try this code
if (File.Exists(Server.MapPath(filename)))
Check if a file exists on the server
In my test, it returned YES and worked well. Did you put "SPU01_Dates.rdlx" file in root folder？
In the development environment, it returned YES, and when I deployed it to IIS, it returned NO. I found that during the deployment process, the rdlx file was not deployed with the project, so I recreated one in the deployed folder, and it returned YES.
The test proves that AppDomain.CurrentDomain.BaseDirectory is the most accurate way to get the file path. When you test this code in IIS, does it return NO or empty? Returning empty means that this piece of code has not been executed.
I have an application that allows the user to upload a file (saving it to in a folder located in the wwwroot of the ASPNETCORE application). From here they can make edits to it and then they can choose to export the file as a csv/ xml/ xlsx which downloads the file to the user's 'downloads' folder.
While debugging in Visual Studio this all works fine however when I publish and deploy the application to IIS I am getting the exception
Error saving file C:\windows\system32\config\systemprofile\Downloads(FILE NAME)
Could not find part of the path C:\windows\system32\config\systemprofile\Downloads(FILE NAME)
This is the current way I am getting the downloads folder:
FileInfo file = new FileInfo(Path.Combine(Environment.ExpandEnvironmentVariables(#"%USERPROFILE%\Downloads"), data.Filename + "." + data.FileType));
However I have also tried the solution that Hans Passant has answered to a similar question here. Both solutions worjk fine while debugging locally however as soon as I publish them, this one produces the exception:
Value cannot be null. Parameter name: path1
Which I presume is thrown at this point here when I try and save the file to the user's download folder.
using (var package = new ExcelPackage(file))
{
var workSheet = package.Workbook.Worksheets.Add("ExportSheet");
workSheet.Cells.LoadFromCollection(exports, true);
package.Save();
}
I don't really know how I would be able to reproduce these exceptions seeing as locally using Visual Studio it all works fine.
Has anyone else came across this issue while trying to download a file?
UPDATE: When the application is running on IIS, it seems to be using that as the user profile instead of the actually user, so when it tries to navigate to the Downloads folder, it cannot find it. How can I force it to use the user's profile?
LoadUserProfile is already set to True.
Web applications have no knowledge of the end-user's computer's filesystem!
So using Environment.GetFolderPath or Environment.ExpandEnvironmentVariables in server side code will only reveal the server-side user (i.e. the Windows Service Identity)'s profile directories which is completely separate and distinct from your web-application's actual browser-based users OS user profile.
As a simple thought-experiment: consider a user running a weird alien web-browser on an even more alien operating system (say, iBrowse for the Amiga!) - the concept of a Windows-shell "Downloads" directory just doesn't exist, and yet here they are, browsing your website. What do you expect your code would do in this situation?
To "download" a file to a user, your server-side web-application should serve the raw bytes of the generated file (e.g. using HttpResponse.TransmitFile) with the Content-Disposition: header to provide a hint to the user's browser that they should save the file rather than try to open it in the browser.
I have an app with which at startup it downloads a file from a remote location (through the net) and parses it's contents.
I am trying to speed up the process of startup as the bigger the file gets the slower the app starts.
As a way to speed up the process I thought of getting the last modified date of the file and if it is newer from the file on the user's pc then and only then download it.
I have found many ways to do it online but none of them are in C# (for windows store apps). Does anybody here know of a way of doing this without the need to download the file? If I am to download the file then the process is sped up at all.
My C# code for downloading the file currently is this
const string fileLocation = "link to dropbox";
var uri = new Uri(fileLocation);
var downloader = new BackgroundDownloader();
StorageFile file = await ApplicationData.Current.LocalFolder.CreateFileAsync("feedlist.txt",CreationCollisionOption.ReplaceExisting);
DownloadOperation download = downloader.CreateDownload(uri, file);
await download.StartAsync();
If it helps the file is stored in dropbox but if any of you guys have a suggestion for another free file hosting service I am open to suggestions
Generally, you can check the file time by sending HEAD request and parsing/looking HTTP header response for a Last-Modified filed. The remote server should support it and DropBox does not support this feature for direct links (only via API). But DropBox have another feature, the headers have the etag field. You should store it and check in the next request. If it changed - the file has been changed too. You can use this tool to check the remote file headers.
The problem:
My company puts out a monthly newsletter which I host on our internal website. I have a page for the author of the newsletter to upload the latest version. Once the author has uploaded the latest newsletter, he sends a broadcast email to announce the new newsletter. Employees invariably check the new newsletter and send feedback to the author with corrections that need to be made.
Once the author has made the necessary corrections (typically within an hour of sending the broadcast email), he revisits my page and replaces the latest version with the updated newsletter.
Immediately following the replacement (or update, if you will) of the newsletter, anyone attempting to access it gets a 500 - Internal Server Error.
My IT guy who maintains the server cannot delete/rename/move the file because of a permissions error and has to do a lot of convoluted things to get the file deleted (and once the file is deleted, the author of the newsletter can re-upload the corrected copy and it works fine.
My IT guy and I are pretty sure that the problem stems from that I'm trying to replace the file while IIS is actively serving it to users (which I thought of and thought that I had coded against happening).
The code that runs the replacement is as follows:
Protected Sub ReplaceLatestNewsletter()
Dim dr As DataRow
Dim sFile As String
Dim mFileLock As Mutex
Try
If Me.Archives.Rows.Count > 0 Then
dr = Me.Archives.Rows(0)
sFile = dr("File").ToString
If dr("Path").ToString.Length > 0 Then
mFileLock = New Mutex(True, "MyMutexToPreventReadsOnOverwrite")
Try
mFileLock.WaitOne()
System.IO.File.Delete(dr("Path").ToString)
Catch ex As Exception
lblErrs.Text = ex.ToString
Finally
mFileLock.ReleaseMutex()
End Try
End If
fuNewsletter.PostedFile.SaveAs(Server.MapPath("~/Newsletter/archives/" & sFile))
End If
Catch ex As Exception
lblErrs.Text = ex.ToString
End Try
dr = Nothing
sFile = Nothing
mFileLock = Nothing
End Sub
I thought the Mutex would take care of this (although after re-reading documentation I'm not sure I can actually use it like I'm trying to). Other comments on the code above:
Me.Archives is a DataTable stored in ViewState
dr("File").ToString is the filename (no path)
dr("Path").ToString is the full local machine path and filename (i.e., 'C:\App_Root\Newsletters\archives\20120214.pdf')
The filenames of the newsletters are set to "YYYYMMDD.pdf" where YYYYMMDD is the date (formatted) of the upload.
In any case, I'm pretty sure that the code above is not establishing an exclusive lock on the file so that the file can be overwritten safely.
Ultimately, I would like to make sure that the following happens:
If IIS is currently serving the file, wait until IIS has finished serving it.
Before IIS can serve the file again, establish an exclusive lock on the file so that no other process, thread, user (etc.) can read from or write to the file.
Either delete the file entirely and write a new file to replace it or overwrite the existing file with the new content.
Remove the exclusive lock so that users can access the file again.
Suggestions?
Also, can I use a Mutex to get a mutually exclusive lock on a file in the Windows filesystem?
Thank you in advance for your assistance and advice.
EDIT:
The way that the links for the newsletter are generated is based on the physical filename. The method used is:
Get all PDF files in the "archives" directory. For each file:
Parse the date of publication from the filename.
Store the date, the path to the file, the filename, and a URL to each file in a DataRow in a DataTable
Sort the DataTable by date (descending).
Output the first row as the current issue.
Output all subsequent rows as "archives" organized by year and month.
UPDATE:
In lieu of not being able to discern when all existing requests for that file have completed, I took a closer look at the first part of #Justin's answer ("your mutex will only have an effect if the process that reads from the file also obtains the same mutex.")
This led me to Configure IIS7 to server static content through ASP.NET Runtime and the linked article in the accepted answer.
To that end, I have implemented a handler for all PDF files which implements New Mutex(True, "MyMutexToPreventReadsOnOverwrite") to ensure that only one thread is doing something with the PDF at any given time.
Thank you for you answer, #Justin. While I did not wind up using the implementation you suggested, your answer pointed me towards an acceptable solution.
Your mutex will only have an effect if the process that reads from the file also obtains the same mutex. What is the method used to serve up the file? Is ASP.Net used or is this just a static file?
My workflow would be a little different:
Write the new newsletter to a new file
Have IIS start serving up the new file instead of the old one for the given Newsletter url
Delete the old file once all existing requests for that file have completed
This requires no locking and also means that we don't need to wait for requests for the current file be completed (something which could potentially take an indefinite amount of time if people keep on making new requests). The only interesting bit is step 2 which will depend on how the file is served - the easiest way would probably be to either set up a HTTP redirect or use URL rewriting
HTTP Redirect
A HTTP Redirect is where the server tells the client to look in a different place when it gets a request for a given resource so that the browser URL is automatically updated to match the new location. For example if the user requested http://server/20120221.pdf then they could be automatically redirected to another URL such as http://server/20120221_v2.pdf (the URL shown in the browser would change however the URL they need to type in would not).
You can do this in IIS 7 using the httpRedirect configuration element, for example:
<configuration>
<system.webServer>
<httpRedirect enabled="true" exactDestination="true" httpResponseStatus="Found">
<!-- Note that I needed to add a * in for IIS to accept the wildcard even though it isn't used in this case -->
<add wildcard="*20120221.pdf" destination="20120221_v2.pdf" />
</httpRedirect>
</system.webServer>
</configuration>
The linked page shows how to change these settings from ASP.Net
Url Rewriting
Alternatively IIS can be set up to automatically serve up the content of a different file for a given URL without the client (the browser) ever knowing the difference. This is called URL rewriting and can be done in IIS using something like this however it does require that additional components be installed to IIS to work.
Using a HTTP Redirect is probably the easiest method.
I have written an ASP.NET web page with C# behind that runs an existing vb script.
The idea is that the user uploads an Excel spreadsheet (.xls) using the web page, the C# does a few basic checks on the file (file type, file name etc) then saves the .xls to a network location.
The C# then passes the network path of the .xls to the vb script, which gets the required information from the .xls to create a .csv file.
Finally the .csv is passed into a stored procedure and uploaded to a database table.
The problem is that all this runs perfectly when I run the webpage locally on my machine. However when I upload the page to the webserver it does not seem to execute the vb script; instead it just sits there waiting for the script to exit.
Some quick info:
Excel is installed on the web server
The website is set to execute scripts and executables
The script is currently set to 'run as' my personal domain login (this has to change) which has admin on the web server
If I run the script on the webserver using the cmd prompt it works
I'd really appreciate any ideas on what might be going wrong... seriously, I'm pulling my hair out over this one and will consider any idea, no matter how crazy... but, and it's a big one, despite the fact that that there are many other ways of achieving the same result, I'm afraid that for a number of reasons this is what I have to work with :)
Edit
Here is how I call the script
try
{
System.Security.SecureString password = new System.Security.SecureString();
string uspw = "mypassword";
foreach (char c in uspw)
{
password.AppendChar(c);
}
Process scriptProc = new Process();
scriptProc.StartInfo.FileName = #"cscript";
scriptProc.StartInfo.Arguments = scriptPath + " //Nologo " + uploadPath + xlsFileName;
scriptProc.StartInfo.WindowStyle = ProcessWindowStyle.Minimized;
scriptProc.StartInfo.UserName = "myusername";
scriptProc.StartInfo.Password = password;
scriptProc.StartInfo.UseShellExecute = false;
scriptProc.Start();
scriptProc.WaitForExit();
scriptProc.Close();
}
catch...
All of the file paths are relative.
The code seems to fail when the script is called. You can clearly see the page waiting for the script to finish. However if you watch the task manager on the web server neither cscript or excel start to run.
I've also stuck a message box right at the start of the script which does not get displayed
Edit 2
It turns out that cscript is running, I just needed to tick the 'All Users' check box in the task manager... I'm still none the wiser though!
Thanks so much in advance
Sounds like you are using automation to control the Excel application itself?
Some quick info:
Excel is installed on the web server
That is generally a bad idea, because the Excel application is not an application that is intended to be automated by a server. Thing might hang because the application is waiting for user input in a dialog somewhere. And it's not scalable for handling operations from multiple users simultaneously.
If the final goal is to extract the data from the excel file and put it in an sql server, I would rather suggest that you use the Jet OLEDB provider to retrieve the data from the excel file, either from your web application, and letting that feed the data into sql server, or let the sql server do it directly. If there is a lot of data in the excel file, the latter might be the best choice
Without seeing the code this is a blind guess - I suggest you check how you are specifying the path to the vb script - make sure you are not using an absolute path, and that the file is in the same location relative to the C# page on the server as it is on your machine.