When uploading files to a server what information should be provided to the user for feedback? I have created a website that allows users to upload files to a server. I would think a progress bar would be nice or at the very least a message to let the users know that the process was successful or not. Another issue is how do I know that the operation was successful? Right now the only thing I can think of is to check if the files exist after they are saved. I am using C# .NET 2.0 on the server side. Here is an example of the code I have for saving the files...
private void fileUpload(HttpContext context)
{
string stgDir = #"myDir",
fullPath;
HttpFileCollection hfc = context.Request.Files;
for(int i = 0; i < hfc.Count; i++)
{
fullPath = Path.Combine(BASE_PATH, stgDir);
if(!Directory.Exists(fullPath))
{
Directory.CreateDirectory(fullPath);
}
if(hfc[i].ContentLength > 0)
{
fullPath = Path.Combine(fullPath,hfc[i].FileName);
hfc[i].SaveAs(fullPath);
}
}
}
If you don't get an exception is very unlikely that there was an error saving the file, so, add a try catch and show your user an error if exception is catch, or just a friendly message indicating the file was uploaded.
Regarding the info as feedback, that's up to you and what you would like the user to know, maybe success message and a link to the file would be enough.
Related
In some case, a user might not want the chrome custom tab to show up in their browsing history. Is there any way the app could tell the Chrome Custom Tab to display the webpage in incognito mode, and avoid storing that URL in the user normal browsing history?
If that's currently not possible, where could someone submit a feature request for that?
Thanks!
It is possible now. For example in C#:
try
{
string dataFolder = "C:\userFolder"; // If you need to maintain your browser session, you can configure a user data directory
string urlToOpen = "https://shalliknow.com"; // replace your url to open
Process process = new Process();
process.StartInfo.FileName = #"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe";
process.StartInfo.Arguments = $"--new-window={urlToOpen} --start-maximized --incognito --user-data-dir=\"{ dataFolder}\""; // SSH new Chrome
process.Start();
}
catch (Exception ex)
{
Console.Writeline("Exception while opening link in browser");
}
The source of this code, as well as a list of command line arguments for chrome.exe can be found here:
https://shalliknow.com/articles/en-scs-how-to-open-chrome-in-incognito-mode-programmatically-in-csharp
I am trying to read a text file and display it on plage. This is what I did. But I am getting error
The process cannot access the file
'D:\wwwroot\TestProject\Logs\TestLog.log' because it is being used by
another process.
Controller Code
Array LogFileData = null;
var logFileNameWithPath = Server.MapPath("D:\wwwroot\TestProject\Logs\TestLog.log");
if (System.IO.File.Exists(logFileNameWithPath))
{
LogFileData = System.IO.File.ReadAllLines(logFileNameWithPath);
}
ViewBag.logFileContent = LogFileData;
View Code
#if (ViewBag.logFileContent != null)
{
foreach (string dataLine in ViewBag.logFileContent)
{
#dataLine
<br />
}
}
The log file is created and used by a service. My code works when I stop service. But I am not trying to write to file exclusively at the same time service is writing to it. Infact I am trying to read at a time when service is not writing to it. Any advice on how can I fix this? THanks.
Generally, you need to specify the "access mode" when you try to read the file. Please take a look here. Try to open the file into a FileStream with appropriate access.
I will post some code when I can.
I'm trying to upload a large file to a document library, but it fails after just a few seconds. The upload single document fails silently, upload multiple just shows a failed message. I've turned up the file size limit on the web application to 500MB, and the IIS request length to the same (from this blog), and increased the IIS timeout for good measure. Are there any other size caps that I've missed?
Update I've tried a few files of various sizes, anything 50MB or over fails, so I assume something somewhere is still set to the webapp default.
Update 2 Just tried uploading using the following powershell:
$web = Get-SPWeb http://{site address}
$folder = $web.GetFolder("Site Documents")
$file = Get-Item "C:\mydoc.txt" // ~ 150MB
$folder.Files.Add("SiteDocuments/mydoc.txt", $file.OpenRead(), $false)
and get this exception:
Exception calling "Add" with "3" argument(s): "<nativehr>0x80070003</nativehr><nativestack></nativestack>There is no file with URL 'http://{site address}/SiteDocuments/mydoc.txt' in this Web."
which strikes me as odd as of course the file wouldn't exist until it's been uploaded? N.B. while the document library has the name Site Documents, it has the URL SiteDocuments. Not sure why...
Are you sure you updated the right webapp? Is the filetype blocked by the server? Is there adequate space in your content database? I would check ULS logs after that and see if there is another error since it seems you hit the 3 spots you would need too update.
for uploading a large file, you can use the PUT method instead of using the other ways to upload a document.
by using a put method you will save the file into content database directly. see the example below
Note: the disadvantage of the code below is you cannot catch the object that is responsible for uploading directly, on other word, you cannot update the additional custom properties of the uploaded document directly.
public static bool UploadFileToDocumentLibrary(string sourceFilePath, string targetDocumentLibraryPath)
{
//Flag to indicate whether file was uploaded successfuly or not
bool isUploaded = true;
try
{
// Create a PUT Web request to upload the file.
WebRequest request = WebRequest.Create(targetDocumentLibraryPath);
//Set credentials of the current security context
request.Credentials = CredentialCache.DefaultCredentials;
request.Method = “PUT”;
// Create buffer to transfer file
byte[] fileBuffer = new byte[1024];
// Write the contents of the local file to the request stream.
using (Stream stream = request.GetRequestStream())
{
//Load the content from local file to stream
using (FileStream fsWorkbook = File.Open(sourceFilePath, FileMode.Open, FileAccess.Read))
{
//Get the start point
int startBuffer = fsWorkbook.Read(fileBuffer, 0, fileBuffer.Length);
for (int i = startBuffer; i > 0; i = fsWorkbook.Read(fileBuffer, 0, fileBuffer.Length))
{
stream.Write(fileBuffer, 0, i);
}
}
}
// Perform the PUT request
WebResponse response = request.GetResponse();
//Close response
response.Close();
}
catch (Exception ex)
{
//Set the flag to indiacte failure in uploading
isUploaded = false;
}
//Return the final upload status
return isUploaded;
}
and here are an example of calling this method
UploadFileToDocumentLibrary(#”C:\test.txt”, #”http://home-vs/Shared Documents/textfile.pdf”);
I have a very unusual problem.
I'm trying to create a simple database (6 tables, 4 of which only have 2 columns).
I'm using an in-house database library which I've used in a previous project, and it does work.
However with my current project there are occasional bugs. Basically the database isn't created correctly. It is added to the sdcard but when I access it I get a DatabaseException.
When I access the device from the desktop manager and try to open the database (with SQLite Database Browser v2.0b1) I get "File is not a SQLite 3 database".
UPDATE
I found that this happens when I delete the database manually off the sdcard.
Since there's no way to stop a user doing that, is there anything I can do to handle it?
CODE
public static boolean initialize()
{
boolean memory_card_available = ApplicationInterface.isSDCardIn();
String application_name = ApplicationInterface.getApplicationName();
if (memory_card_available == true)
{
file_path = "file:///SDCard/" + application_name + ".db";
}
else
{
file_path = "file:///store/" + application_name + ".db";
}
try
{
uri = URI.create(file_path);
FileClass.hideFile(file_path);
} catch (MalformedURIException mue)
{
}
return create(uri);
}
private static boolean create(URI db_file)
{
boolean response = false;
try
{
db = DatabaseFactory.create(db_file);
db.close();
response = true;
} catch (Exception e)
{
}
return response;
}
My only suggestion is keep a default database in your assets - if there is a problem with the one on the SD Card, attempt to recreate it by copying the default one.
Not a very good answer I expect.
Since it looks like your problem is that the user is deleting your database, just make sure to catch exceptions when you open it (or access it ... wherever you're getting the exception):
try {
URI uri = URI.create("file:///SDCard/Databases/database1.db");
sqliteDB = DatabaseFactory.open(myURI);
Statement st = sqliteDB.createStatement( "CREATE TABLE 'Employee' ( " +
"'Name' TEXT, " +
"'Age' INTEGER )" );
st.prepare();
st.execute();
} catch ( DatabaseException e ) {
System.out.println( e.getMessage() );
// TODO: decide if you want to create a new database here, or
// alert the user if the SDCard is not available
}
Note that even though it's probably unusual for a user to delete a private file that your app creates, it's perfectly normal for the SDCard to be unavailable because the device is connected to a PC via USB. So, you really should always be testing for this condition (file open error).
See this answer regarding checking for SDCard availability.
Also, read this about SQLite db storage locations, and make sure to review this answer by Michael Donohue about eMMC storage.
Update: SQLite Corruption
See this link describing the many ways SQLite databases can be corrupted. It definitely sounded to me like maybe the .db file was deleted, but not the journal / wal file. If that was it, you could try deleting database1* programmatically before you create database1.db. But, your comments seem to suggest that it was something else. Perhaps you could look into the file locking failure modes, too.
If you are desperate, you might try changing your code to use a different name (e.g. database2, database3) each time you create a new db, to make sure you're not getting artifacts from the previous db.
I am trying to read an Excel sheet using C# which is to be loaded by end user from fileUpload control.
I am writing my code to save the file on server in event handler of another button control(Upload). But when I click on Upload Button I am getting this exception:
The process cannot access the file 'E:\MyProjectName\App_Data\sampledata.xlsx' because it is being used by another process.
Here is the code that I have used in event handler:
string fileName = Path.GetFileName(file_upload.PostedFile.FileName);
string fileExtension = Path.GetExtension(file_upload.PostedFile.FileName);
string fileLocation = Server.MapPath("~/App_Data/" + fileName);
//if (File.Exists(fileLocation))
// File.Delete(fileLocation);
file_upload.SaveAs(fileLocation);
Even deleting the file is not working, throwing the same exception.
Make sure, some other process is not accessing that file.
This error might occurs whenever you are trying to upload file, without explicitly removing it from memory.
So try this:
try
{
string fileName = Path.GetFileName(file_upload.PostedFile.FileName);
string fileExtension = Path.GetExtension(file_upload.PostedFile.FileName);
string fileLocation = Server.MapPath("~/App_Data/" + fileName);
//if (File.Exists(fileLocation))
// File.Delete(fileLocation);
file_upload.SaveAs(fileLocation);
}
catch (Exception ex)
{
throw ex.Message;
}
finally
{
file_upload.PostedFile.InputStream.Flush();
file_upload.PostedFile.InputStream.Close();
file_upload.FileContent.Dispose();
//Release File from Memory after uploading
}
The references are hanging in memory, If you are using Visual Studio try with Clean Solution and Rebuild again, if you are in IIS, just do a recycle of your application.
To avoid this problems try to dispose the files once you used them, something like:
using(var file= new FileInfo(path))
{
//use the file
//it will be automatically disposed after use
}
If i have understood the scenario properly.
For Upload control, I don't think you have to write code for Upload Button. When you click on your button,your upload control has locked the file and using it so it is already used by one process. Code written for button will be another process.
Prior to this, check whether your file is not opened anywhere and pending for edit.