I have a try catch statement which handles reading a list of xml files and outputs them to csv files.
Now I want to be able to move faulty xml files to a different folder from the healthy files but am not sure how to do it.
What I have got so far is as below:
bool faultyYN = false;
foreach (string filename in XMLFiles)
{
using (var reader = new StreamReader(filename))
{
string shortFileName = Path.GetFileNameWithoutExtension(filename);
XMLShredder.DataFile df = null;
try
{
var sw = new Stopwatch();
sw.Start();
df = Shredder.ShredDocument(XDocument.Load(reader, LoadOptions.SetLineInfo));
sw.Stop();
var elapsed = sw.ElapsedMilliseconds;
_log.InfoFormat(" Shredded file <{0}> in {1}ms", shortFileName, elapsed);
string outputFileName = Path.Combine(outputDirectory, shortFileName) + ".csv";
sw.Reset();
sw.Start();
using (var writer = new ChunkedShreddedFileWriter(outputFileName))//full file path
{
new DataFileCsvWriter().Write(df,
writer);
}
sw.Stop();
var elapsed2 = sw.ElapsedMilliseconds;
_log.InfoFormat(" Wrote file <{0}> in {1}ms", shortFileName, elapsed2);
}
catch (XmlException e)
{
_log.Error(String.Format("Reading failed due to incorrect structure in XML Document. File Name : <{0}>. Error Message : {1}.", shortFileName, e.Message), e);
faultyYN = true;
}
catch (IOException e)
{
_log.Error(String.Format("Reading failed due to IO Exception. File Name : <{0}>. Error Message : {1}.", shortFileName, e.Message), e);
}
if(bool faultyYN == true)
{
MoveFaultyXML(faultyXMLDirectory, shortFileName);
}
}
TidyUp(XMLFiles);//deletes the files after the process has finished.
}
I have tried adding the Move faulty files to faulty directory after the catch but the files still keep getting deleted.
So basically the method that does not work as I don't know where I should be calling it from is "MoveFaultyXML(faultyXMLDirectory, shortFileName)".
I have read on the net that I shouldn't be using a an exception to branch out but in this case I couldn't think of an alternative solution. The exception has to be thrown for me to know that there is something wrong with the file.
If there is another way of dealing with this which is better practice or if this way works but I am doing it wrong then please help me and I would really appreciate it.
Thanks,
Jetnor.
First solution that comes to my mind would be to:
Move the MoveFaultyXML(faultyXMLDirectory, shortFileName); call to do it within the appropriate catch block:
catch (XmlException e)
{
//log
MoveFaultyXML(faultyXMLDirectory, shortFileName);
}
You don't need the boolean faultyYN.
Now you can create a class representing your XML file (instead of storing just file names in your XMLFiles list):
public class XMLFile
{
public string FileName { get; set; }
public bool Delete { get; set; }
}
And set the Delete flag to 'false' if you move the file.
In the TidyUp delete only files with this flag set to 'true'.
An alternative solution would be to:
Replace foreach() with
for(int i=XMLFiles.Count - 1; i >= 0; i--)
{
string filename = XMLFiles[i];
//the rest of your code
}
Change the catch block with the XMLException to:
catch (XmlException e)
{
//log
MoveFaultyXML(faultyXMLDirectory, shortFileName);
XMLFiles.RemoveAt(i);
}
This way when you get to CleanUp function, any files that were moved are no longer on the list to be deleted.
The `XmlException' is thrown when the XML is incorrect, so it is inside this catch block that you have to call your MoveFaultyXML.
Additional Notes:
Don't add YN to boolean names. Use something like xmlIsFaulty = true. This makes the code easier to read because then you have conditional statements like
if(xmlIsFaulty){MoveFaultyXml();}
which even a non-programmar can understand.
In this code, you're redeclaring the faultyYN variable which should given an error.
if(bool faultyYN == true)
{
MoveFaultyXML(faultyXMLDirectory, shortFileName);
}
After you've declared the variable at the start of the method, you do not need to declare it again.
This is because TidyUp(XMLFiles); still gets executed after your exception is caught, you can move TidyUp(XMLFiles); to within the try block or only call it in catch blocks which are needed.
Related
EDIT:
My problem has been solved thanks to the user Chris Larabell, thank you to all that responded.
The issue that is happening with my code is that when the said file is not present in the Desktop directory, the console will close and will not go to the else statement for what happens when the file is not present. When the file is present however, the console will work completely fine, it is just the else statement.
Here is my code that is being used.
if (inputDrive == "search.system")
{
try
{
string Desktop = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory);
string DeleteFile = #"delete.txt";
string[] fileList = System.IO.Directory.GetFiles(Desktop, DeleteFile);
foreach (string file in fileList)
{
if (System.IO.File.Exists(file))
{
System.IO.File.Delete(file);
Console.WriteLine("File has been deleted");
Console.ReadLine();
}
else
{
Console.Write("File could not be found");
Console.ReadLine();
}
}
}
catch (System.IO.FileNotFoundException)
{
Console.WriteLine("search has encountered an error");
Console.ReadLine();
}
}
What I am trying to accomplish is to find a file through the Desktop directory with the name of 'delete.txt' and to delete it when the user enters "search.system". the console would then say back to you that the file has been deleted. If the file has not been found, it would say that "the file could not be found" back to you through console. If an error would to occur, it would go to catch and say "search has encountered an error"
I also want to say that I am sorry if this code is messy and/or if this is completely wrong from what I am trying to accomplish. I am new to C#, and new to coding in general.
You would want to put an if statement to check that the fileList length is > 0. If the file length is zero, the file was not found. Otherwise, you can proceed to delete the file.
Also, don’t be discouraged as a new coder. Set a breakpoint at the line where you use the GetFiles() method and step (F11) to the next line. Hover your cursor over the fileList variable and see if the number of items in the array is zero.
System.IO.Directory.GetFiles()
It looks like you are simply looking for a specific file by name and deleting it if it exists. You could simplify your code by doing this:
if (inputDrive == "search.system")
{
try
{
string Desktop = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory);
string DeleteFile = #"delete.txt";
string filePath = System.IO.Path.Combine(Desktop, DeleteFile);
if (System.IO.File.Exists(filePath))
{
System.IO.File.Delete(filePath);
Console.WriteLine("File has been deleted");
Console.ReadLine();
}
else
{
Console.Write("File could not be found");
Console.ReadLine();
}
}
catch (System.Exception ex)
{
Console.WriteLine($"search has encountered an error: {ex}");
Console.ReadLine();
}
}
After searching and trying the different ways I found I either wasn't happy with the way I was doing the code or it didn't work right for me. I'm new at programming so my understanding is limited. Please keep in mind with the answer.
I want to read a .csv file line by line and skipping lines that are blank. With the contents of the lines I want to put into a list of object. I have everything working except for the skipping line part. Also any feedback about improving any parts of my code are all welcome. I like constructive criticism.
public void CardaxCsvFileReader()
{
string cardaxCsvPath = (#"C:\Cardax2WkbTest\Cardax\CardaxTable.csv");
try
{
using (System.IO.StreamReader cardaxSR =
new System.IO.StreamReader(System.IO.File.OpenRead(cardaxCsvPath)))
{
string line = "";
string[] value = line.Split(',');
while (!cardaxSR.EndOfStream)
{ // this commented out part is what I would like to work but doesn't seem to work.
line = cardaxSR.ReadLine();//.Skip(1).Where(item => !String.IsNullOrWhiteSpace(item));
value = line.Split(',');
if (line != ",,,,,") // using this as temp to skip the line because the above commented out part doesn't work.
{
CardaxDataObject cardaxCsvTest2 = new CardaxDataObject();
cardaxCsvTest2.EventID = Convert.ToInt32(value[0]);
cardaxCsvTest2.FTItemID = Convert.ToInt32(value[1]);
cardaxCsvTest2.PayrollNumber = Convert.ToInt32(value[2]);
cardaxCsvTest2.EventDateTime = Convert.ToDateTime(value[3]);
cardaxCsvTest2.CardholderFirstName = value[4];
cardaxCsvTest2.CardholderLastName = value[5];
Globals.CardaxQueryResult.Add(cardaxCsvTest2);
}
}
}
}
catch (Exception)
{
myLog.Error("Unable to open/read Cardax simulated punch csv file! " +
"File already open or does not exist: \"{0}\"", cardaxCsvPath);
}
EDITED
If you are lines are not truly blank and contain commas, you can split with RemoveEmptyEntries option and then check the column count.
while (!cardaxSR.EndOfStream)
{ // this commented out part is what I would like to work but doesn't seem to work.
line = cardaxSR.ReadLine();//.Skip(1).Where(item => !String.IsNullOrWhiteSpace(item));
value = line.Split(new char[] {','}, StringSplitOptions.RemoveEmptyEntries); // <-- Remove empty columns while splitting. It has a side-effect: Any record with just a single blank column will also get discarded by the if that follows.
if (value.length < 6)
continue;
CardaxDataObject cardaxCsvTest2 = new CardaxDataObject();
cardaxCsvTest2.EventID = Convert.ToInt32(value[0]);
cardaxCsvTest2.FTItemID = Convert.ToInt32(value[1]);
cardaxCsvTest2.PayrollNumber = Convert.ToInt32(value[2]);
cardaxCsvTest2.EventDateTime = Convert.ToDateTime(value[3]);
cardaxCsvTest2.CardholderFirstName = value[4];
cardaxCsvTest2.CardholderLastName = value[5];
Globals.CardaxQueryResult.Add(cardaxCsvTest2);
}
Another improvement feedback I have: When you catch an exception, it's a good practice to log the exception in addition to your custom error line. A custom error line might be good for say website users, but as a developer running some service you will appreciate the actual exception stack trace. It will help you debug a bug easier.
catch (Exception ex)
{
myLog.Error("Unable to open/read Cardax simulated punch csv file! " +
"File already open or does not exist: \"{0}\".\r\n Exception: {1}", cardaxCsvPath, ex.ToString());
}
Just check if value.Length == 6, this way it'll skip lines which don't contain enough data for your columns
Use a dedicated CSV parser, such as the EasyCSV class available here*:
https://github.com/jcoehoorn/EasyCSV
public void CardaxCsvFileReader()
{
try
{
string cardaxCsvPath = (#"C:\Cardax2WkbTest\Cardax\CardaxTable.csv");
Globals.CardaxQueryResult =
EasyCSV.FromFile(cardaxCsvPath)
.Where(r => r.Any(c => !string.IsNullOrEmpty(c)))
.Select(r => CardaxDataObject() {
cardaxCsvTest2.EventID = int.Parse(r[0]),
cardaxCsvTest2.FTItemID = int.Parse(r[1]),
cardaxCsvTest2.PayrollNumber = int.Parse(r[2]),
cardaxCsvTest2.EventDateTime = DateTinme.Parse(r[3]),
cardaxCsvTest2.CardholderFirstName = r[4],
cardaxCsvTest2.CardholderLastName = r[5]
}).ToList();
}
catch (Exception)
{
myLog.Error("Unable to open/read Cardax simulated punch csv file! " +
"File already open or does not exist: \"{0}\"", cardaxCsvPath);
}
}
I also recommend re-thinking how you structure this. The code below is better practice:
public IEnumerable<CardaxDataObject> ReadCardaxCsvFile(string filename)
{
//no try block at this level. Catch that in the method that calls this method
return EasyCSV.FromFile(cardaxCsvPath)
.Where(r => r.Any(c => !string.IsNullOrEmpty(c)))
// You may want to put a try/catch inside the `Select()` projection, though.
// It would allow you continue if you fail to parse an individual record
.Select(r => CardaxDataObject() {
cardaxCsvTest2.EventID = int.Parse(r[0]),
cardaxCsvTest2.FTItemID = int.Parse(r[1]),
cardaxCsvTest2.PayrollNumber = int.Parse(r[2]),
cardaxCsvTest2.EventDateTime = DateTinme.Parse(r[3]),
cardaxCsvTest2.CardholderFirstName = r[4],
cardaxCsvTest2.CardholderLastName = r[5]
});
}
Suddenly the method boils down to one statement (albeit a very long statement). Code like this is better, because it's more powerful, for three reasons: it's not limited to using just the one input file, it's not limited to only sending it's output to the one location, and it's not limited to only one way to handle errors. You'd call it like this:
try
{
string cardaxCsvPath = (#"C:\Cardax2WkbTest\Cardax\CardaxTable.csv");
Globals.CardaxQueryResult = ReadCardaxCsvFile(cardaxCsvPath).ToList();
}
catch (Exception)
{
myLog.Error("Unable to open/read Cardax simulated punch csv file! " +
"File already open or does not exist: \"{0}\"", cardaxCsvPath);
}
or like this:
try
{
string cardaxCsvPath = (#"C:\Cardax2WkbTest\Cardax\CardaxTable.csv");
foreach (var result in ReadCardaxCsvFile(cardaxCsvPath))
{
Globals.CardaxQueryResult.Add(result);
}
}
catch (Exception)
{
myLog.Error("Unable to open/read Cardax simulated punch csv file! " +
"File already open or does not exist: \"{0}\"", cardaxCsvPath);
}
I also recommend against using a Globalsclass like this. Find a more meaningful object with which you can associate this data.
* Disclaimer: I am the author of that parser
I have a C# application which uses log4net to write some log outputs in a file names "logfile.txt" residing in the application directory. I want to empty the contents of the file as soon as it reaches a size of 10GB.
For that I'm using a timer which keeps checking whether the size of the file crosses 10GB.
But I cannot perform any operation on "logfile.txt" since it is being used by other threads to write log outputs and it's throwing me,
System.IO.IOException "The process cannot access the file 'C:\Program Files\MyApps\TestApp1\logfile.txt' because it is being used by another process."
Here is the code of the timer which checks the size of the file "logfile.txt"
private void timer_file_size_check_Tick(object sender, EventArgs e)
{
try
{
string log_file_path = "C:\\Program Files\\MyApps\\TestApp1\\logfile.txt";
FileInfo f = new FileInfo(log_file_path);
bool ex;
long s1;
if (ex = f.Exists)
{
s1 = f.Length;
if (s1 > 10737418240)
{
System.GC.Collect();
System.GC.WaitForPendingFinalizers();
File.Delete(log_file_path);
//File.Create(log_file_path).Close();
//File.Delete(log_file_path);
//var fs = new FileStream(log_file_path, FileMode.Truncate);
}
}
else
{
MDIParent.log.Error("Log file doesn't exists..");
}
}
catch (Exception er)
{
MDIParent.log.Error("Exceptipon :: " + er.ToString());
}
}
You shouldn't delete a log file on your own because log4net can do it for you. If you use RollingFileAppender you can specify the maximum file size (maximumFileSize property). Additionally if you set maxSizeRollBackups property to 0, then the log file will be truncated when it reaches the limit. Please look at this question for an example.
I am making a software that will move files from the downloads folder to a specific sub folder in a directory. The sub folder is selected by the user by a combobox. I keep getting this error: System.IO.IOException: Cannot create a file when that file already exists. Also, these error come up on people's computer who install my program...exceptions and things. How do i turn it off. Also, why do i get this error? Here is my code:
string pathUser4 = Environment.GetFolderPath(Environment.SpecialFolder.UserProfile);
string pathDownload4 = (pathUser4 + #"\Downloads\");
string sourceFile = pathDownload4 + listBox1.Text;
string pathdoc5 = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
string pathDownload5 = (pathdoc5 + #"\iracing\setups\");
string destinationFile = pathDownload5 + comboBox1.Text;
File.Move(sourceFile, destinationFile);
if (comboBox1.Text == "Select File Destination")
{
MessageBox.Show("Please Select A Destination Folder", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
Each File.Move should be wrapped in a try/catch block as you can never expect an IO operation to execute without error. It could be something as simple as the user having a file handle open, or the file existing in the destination folder, either way, you don't want a single file to throw an exception that stops the entire operation. You will want to catch the exceptions and log them either to an error log file or to the event log, this way you can see the errors that occurred but it will not interrupt anything.
Secondly, for any desktop application I would add global error handling to log any uncaught errors. You can do this by putting this code at the beginning of your program,
AppDomain.CurrentDomain.UnhandledException += (a, exception) => File.AppendAllText("errorlog.txt", exception.ToString() + "\n"
This will keep the user from ever seeing ugly exceptions being thrown. Also be sure you are not giving the users the .pdb files as this will cause exceptions to contain paths of the computer it was compiled on which can contain your username and other sensitive information you wouldn't want a client to see.
You can register the global exception handling when the main window is initialized, you want it to be the first thing you do before any thing else because again you never know when an exception will be thrown so you have to think defensively.
public partial class MainWindow : Window
{
public MainWindow()
{
AppDomain.CurrentDomain.UnhandledException += (a, exception) => File.AppendAllText("errorlog.txt", exception.ToString() + "\n");
InitializeComponent();
}
}
C# uses exceptions extensively so it will be good concept for you to study up on if you are not familiar with this type of error handling. All exceptions derive from the Exception class so when you write catch (Exception e) this will catch all exceptions (because a base reference can hold an object of a derived type), however if you know the specific exception a method will throw you can catch a more specific exception (always before the more general catch) and handle it in a specific way. In this example you may have an IOException from the File.Move() that you want to catch and handle differently.
try
{
string pathUser4 = Environment.GetFolderPath(Environment.SpecialFolder.UserProfile);
string pathDownload4 = (pathUser4 + #"\Downloads\");
string sourceFile = pathDownload4 + listBox1.Text;
string pathdoc5 = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
string pathDownload5 = (pathdoc5 + #"\iracing\setups\");
string destinationFile = pathDownload5 + comboBox1.Text;
File.Move(sourceFile, destinationFile);
if (comboBox1.Text == "Select File Destination")
{
MessageBox.Show("Please Select A Destination Folder", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
catch (Exception e)
{
File.AppendAllText("ErrorLog.txt", e.ToString() + "\n");
}
The example code from MSDN for File.Move should get you pointed at the various things you need to deal with, such as an already existing file and basic error handling.
using System;
using System.IO;
class Test
{
public static void Main()
{
string path = #"c:\temp\MyTest.txt";
string path2 = #"c:\temp2\MyTest.txt";
try
{
if (!File.Exists(path))
{
// This statement ensures that the file is created,
// but the handle is not kept.
using (FileStream fs = File.Create(path)) {}
}
// Ensure that the target does not exist.
if (File.Exists(path2))
File.Delete(path2);
// Move the file.
File.Move(path, path2);
Console.WriteLine("{0} was moved to {1}.", path, path2);
// See if the original exists now.
if (File.Exists(path))
{
Console.WriteLine("The original file still exists, which is unexpected.");
}
else
{
Console.WriteLine("The original file no longer exists, which is expected.");
}
}
catch (Exception e)
{
Console.WriteLine("The process failed: {0}", e.ToString());
}
}
}
The error may caused by your code, or by some invalid input.
As #Despertar mentioned, I suggest all the program include error handling and log features in your code. It will be very helpful for your debug.
But I suggest use open source log library, not do it by yourself. For example, log4net, NLog, etc.
I am monitoroing a folder using FileSystemWatcher and deleting the files created under the folder. But my application is throwing me an exception:
File is being used by another application
ifsXmlFileWatcher.Path = "D:\\";
ifsXmlFileWatcher.IncludeSubdirectories = false;
ifsXmlFileWatcher.EnableRaisingEvents = true;
ifsXmlFileWatcher.Created += new FileSystemEventHandler(IfsFileUpload);
private void IfsFileUpload(object sender, System.IO.FileSystemEventArgs e)
{
try
{
{
File.Delete(e.FullPath);
}
}
catch (Exception exp)
{
MessageBox.Show(exp.Message);
}
}
What might be the problem?
I guess it's a timing problem. The FileSystemWatcher fires it's Created event immediately when the file was created. This does not mean that all content is written to the file and it is closed again. So it's just accessed by the process who created it because this process has not finished writing to it yet.
TO delete it you have to wait until writing has finished.
Problem as you know "File is being used by another application".
So it may be your own application using it or some other application in your environment using it. Possible solution can be
You can keep trying deleting it certain number of times i try here as 5 times and then give up/write event somewhere or show message. I posted similar answer here where someone needs to make sure file copied is success How to know that File.Copy succeeded?
private void IfsFileUpload(object sender, System.IO.FileSystemEventArgs e)
{
bool done = false;
string file = e.FullPath;
int i = 0;
while (i < 5)
{
try
{
System.IO.File.Delete(file);
i = 5;
done = true;
}
catch (Exception exp)
{
System.Diagnostics.Trace.WriteLine("File trouble " + exp.Message);
System.Threading.Thread.Sleep(1000);
i++;
}
}
if (!done)
MessageBox.Show("Failed to delte file " + file);
}