Develop Reference

Retrieve Date Information from a .txt file using c#

namespace SimpleLicense
{
class Program
{
static void Main(string[] args)
{
string fileName = #"C:\\Temp\\test.txt";
try
{
// Check if file already exists. If yes, delete it.
if (File.Exists(fileName))
{
File.Delete(fileName);
}
// Create a new file
Directory.CreateDirectory(Path.GetDirectoryName(fileName));
using (StreamWriter sw = File.CreateText(fileName))
{
sw.WriteLine("Thermo Licensing System file");
sw.WriteLine("------------------------------------");
sw.WriteLine("Installed Date: {0}", DateTime.Now.ToString());
DateTime newDate = DateTime.Now.AddDays(31);
sw.WriteLine("License Expires After"+" "+newDate);
sw.WriteLine("Number of Days Remaining ");
sw.Close();
// sw.WriteLine("Add ");
// sw.WriteLine("Done! ");
}
// Write file contents on console.
using (StreamReader sr = File.OpenText(fileName))
{
string s = "";
while ((s = sr.ReadLine()) != null)
{
Console.WriteLine(s);
}
Console.ReadLine();
}
}
catch (Exception Ex)
{
Console.WriteLine(Ex.ToString());
}
}
}
}
Contents of .txt File
Thermo Licensing System file
------------------------------------
Installed Date: 20-05-2014 16:01:42
License Expires After 20-06-2014 16:01:42
Number Of Days Remaining
Hi Everyone,
I have written the above code to store date and time information to a .txt file as given above.I want that the information about the remaining days be stored in .txt file.As you can see today's date is 20-5-2014 and the license expires on 20-6-2014.So 30 should be printed next to Number Of Days Remaining.
If the user changes the system clock,and changes the date to say 21-5-2014, then 29Days should be printed next to Number of Days remaining
I also want that when the application is executed on a particular date, the date should be set to that date ie at installed date and should not change and the remaining days be calculated on the basis of Installed date
Can anyone help me to figure this out?
Thanks

This code will give you the number of days:
int numberOfDays = newDate.Subtract(DateTime.Now).Days;
sw.WriteLine("Number of Days Remaining: " + numberOfDays.ToString());

you can used below menioned code
var Remainingdays=(LicenseExpires-InstalledDate).TotalDays
and if you want in int days then
var Remainingdays=(LicenseExpires-InstalledDate).Days

I assume you want to do time limited version of software?
While code posted in previous answers is technically correct, you probably shouldn't use DateTime.Now as user can tamper with system clock and circumvent your measure. Get current date from another source, like:
http://www.worldtimeserver.com/
This has its disadvantages though, like increased startup time and what if a page or user's connection is down?
Better and easier solution would be to forget about time limitation and limit amount of times application can be started instead. Then you simply load number on opening program and write decreased one on closing.
Also, storing relevant values as plaintext (with helpful user-friendly descriptions no less!) is probably not a good idea as any halfway savvy user may just snoop through files and edit them in any text editor. You may want to use some kind of encryption algorithm like AES:
http://msdn.microsoft.com/pl-pl/library/system.security.cryptography.aes%28v=vs.110%29.aspx

if statements to evaluate multiple file dates

I am new to C# (less than a week), I have the following code that deletes a file on a volume. It is a back up file for an SQL database. And it keeps growing so periodically I have to rename the file and then delete it after a new file is backed up. I need to evaluate if the backup ran and then it is okay to delete the file.
using System;
using System.IO;
class Program
{
static void Main()
{
//
// Delete a file found on the D:\ volume.
// If the file is not found (File doesn't exist),
// then you will get an exception.
//
try
{
File.Delete(#"\\Fabtrol-2\Program Files (x86)\FabTrolBackUp\FT_Trans_Log_Appendedold.BAK"); // Try to delete
Console.WriteLine("Deleted"); // Success
}
catch (IOException ex)
{
Console.WriteLine(ex); // Write error
}
}
}
This is the logic. If I'm asking too much let me know:
If todays date is = Monday and file FT_FabTrol_Sun_Full.BAK ‘s date is less than 2 days old then it is okay to delete the file named FT_Trans_Log_Appendedold.BAK
Else If todays date is = Tuesday and file FT_FabTrol_Mon_Full.BAK ‘s date is less than 2 days old then it is okay to delete the file named FT_Trans_Log_Appendedold.BAK
Else If todays date is = Wednesday and file FT_FabTrol_Tues_Full.BAK ‘s date is less than 2 days old then it is okay to delete the file named FT_Trans_Log_Appendedold.BAK
Else If todays date is = Thursday and file FT_FabTrol_Wed_Full.BAK ‘s date is less than 2 days old then it is okay to delete the file named FT_Trans_Log_Appendedold.BAK
Else If todays date is = Friday and file FT_FabTrol_Thurs_Full.BAK ‘s date is less then 2 days old then it is okay to delete the file named FT_Trans_Log_Appendedold.BAK
Else If todays date is = Saturday and file FT_FabTrol_Fri_Full.BAK ‘s date is less than 2 days old then it is okay to delete the file named FT_Trans_Log_Appendedold.BAK
Else If todays date is = Sunday and file FT_FabTrol_Sat_Full.BAK ‘s date is less than 2 days old then it is okay to delete the file named FT_Trans_Log_Appendedold.BAK

You can simplify that logic greatly with: -
FileInfo info = new FileInfo(#"\\Fabtrol-2\Program Files (x86)\FabTrolBackUp\FT_Trans_Log_Appendedold.BAK");
if(DateTime.Now.AddDays(-2) > info.LastWriteTime.Date)
{
//Delete
}

All you need to do is iterate over all the files in your folder and delete the ones that are older than two days, right (that seems to be what your giant conditional statement comes down to)?
So, use the following line to get all the files in the folder:
string[] files = Directory.GetFiles(<folder name>);
Then, in a loop, iterate over all the file names in files and check, whether they are old enough.
To get the timestamp of the file, use FileInfo and LastWriteTime like this:
if(DateTime.Today - someFileInfoObject.LastWriteTime.Date > new TimeSpan(2,0,0,0))
{
File.Delete();
}

This code 1st checks if the file based on the day is less than 2 days old, then if it is it deletes the file FT_Trans_Log_Appendedold.BAK.
string dir = #"\\Fabtrol-2\Program Files (x86)\FabTrolBackUp\";
string fileName = dir;
switch (DateTime.Now.DayOfWeek)
{
case DayOfWeek.Monday:
fileName += "FT_FabTrol_Sun_Full.BAK";
break;
case DayOfWeek.Tuesday:
fileName += "FT_FabTrol_Mon_Full.BAK";
break;
case DayOfWeek.Wednesday:
fileName += "FT_FabTrol_Tues_Full.BAK";
break;
case DayOfWeek.Thursday:
fileName += "FT_FabTrol_Wed_Full.BAK";
break;
case DayOfWeek.Friday:
fileName += "FT_FabTrol_Thurs_Full.BAK";
break;
case DayOfWeek.Saturday:
fileName += "FT_FabTrol_Fri_Full.BAK";
break;
case DayOfWeek.Sunday:
fileName += "FT_FabTrol_Sat_Full.BAK";
break;
}
FileInfo fi = new FileInfo(fileName);
if (fi.Exists && DateTime.Now.AddDays(-2) > fi.LastWriteTime.Date)
{
(new FileInfo(dir + "FT_Trans_Log_Appendedold.BAK")).Delete();
Console.WriteLine("Deleted");
}

Personally for one weeks experience I would say you've jumped into the deep end.
I'm not going to provide code, rather direct you to improve your learning, this is referred to psuedo code
Look into streamwriter/reader and filewriter and fileinfo.
From this you can then read files, delete/rename/whatever you want really.
You then need to try and understand how could I validate what I'm doing.
Unfortunately for a beginner this is harder than you may think, possibly harder than the first two points for some people. Think from simple onwards, we developers usually over complicate things. This part is actually rather easy so long your file stuff is correct!
You may want to look into unit testing as this may help your validation.

Building on what #Gray commented, the FileInfo object will also let you know if it .Exists or not, alleviating the need to depend on the try/catch to know if a file is still there.
Consider the following:
static void Main()
{
FileInfo fi = new FileInfo(#"\\path\\to\\file.bak");
if(fi.Exists)
{
try
{
//because we can still get errors based on permissions etc.
fi.Delete();
Console.WriteLine("Deleted"); // Success
}
catch (IOException ex)
{
Console.WriteLine(ex); // Write error
}
}
}

Try below code.
string backupFile = #"\\Fabtrol-2\Program Files (x86)\FabTrolBackUp\FT_Trans_Log_Appendedold.BAK";
FileInfo fi = new FileInfo(backupFile);
DateTime fileCreatedDate = File.GetCreationTime(backupFile);
DateTime today = DateTime.Now;
if (today.DayOfWeek != DayOfWeek.Monday && fileCreatedDate > today.AddDays(-2))
{
fi.Delete();
}

Updated my answer to meet your requirements. Kinda weird, but I was bored. May be helpful if just to read.
//2 days
TimeSpan daysToKeep = new TimeSpan(2,0,0,0);
//The folder where the files are kept
DirectoryInfo backupFolder = new DirectoryInfo(#"\\Fabtrol-2\Program Files (x86)\FabTrolBackUp\");
//the Appendold.BAK file
FileInfo backupLog = new FileInfo(backupFolder.FullName + #"\FT_Trans_Log_Appendedold.BAK");
//the base name for the log files
string logName = "FT_FabTrol_{0}_Full.BAK";
//an array for the days of week that are part of the logname
string[] days = { "Sun", "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
//get yesterday's log file name
string yesterdayLog = String.Format(logName, days[(int)DateTime.Today.AddDays(-1).DayOfWeek]);
//create file info
FileInfo logFile = new FileInfo(backupFolder.FullName + yesterdayLog);
//if the file exists, and it is less than 2 days old
try
{
if (logFile.Exists && (DateTime.Today - logFile.LastWriteTime < daysToKeep))
{
backupLog.Delete();
Console.WriteLine("success");
}
else
{
Console.WriteLine("log file either did not exist or is not ready to delete");
}
}
catch(Exception ex)
{
Console.WriteLine(ex.Message);
}

Search String takes a long time the first time only?

No shortage of search for string performance questions out there yet I still can not make heads or tails out of what the best approach is.
Long story short, I have committed to moving from 4NT to PowerShell. In leaving the 4NT I am going to miss the console super quick string searching utility that came with it called FFIND. I have decided to use my rudimentary C# programming skills to try an create my own utility to use in PowerShell that is just as quick.
So far search results on a string search in 100's of directories across a few 1000 files, some of which are quite large, are FFIND 2.4 seconds and my utility 4.4 seconds..... after I have ran mine at least once????
The first time I run them FFIND does it near the same time but mine takes over a minute? What is this? Loading of libraries? File indexing? Am I doing something wrong in my code? I do not mind waiting a little longer but the difference is extreme enough that if there is a better language or approach I would rather start down that path now before I get too invested.
Do I need to pick another language to write a string search that will be lighting fast
I have the need to use this utility to search through 1000 of files for strings in web code, C# code, and another propitiatory language that uses text files. I also need to be able to use this utility to find strings in very large log files, MB size.
class Program
{
public static int linecounter;
public static int filecounter;
static void Main(string[] args)
{
//
//INIT
//
filecounter = 0;
linecounter = 0;
string word;
// Read properties from application settings.
string filelocation = Properties.Settings.Default.FavOne;
// Set Args from console.
word = args[0];
//
//Recursive search for sub folders and files
//
string startDIR;
string filename;
startDIR = Environment.CurrentDirectory;
//startDIR = "c:\\SearchStringTestDIR\\";
filename = args[1];
DirSearch(startDIR, word, filename);
Console.WriteLine(filecounter + " " + "Files found");
Console.WriteLine(linecounter + " " + "Lines found");
Console.ReadKey();
}
static void DirSearch(string dir, string word, string filename)
{
string fileline;
string ColorOne = Properties.Settings.Default.ColorOne;
string ColorTwo = Properties.Settings.Default.ColorTwo;
ConsoleColor valuecolorone = (ConsoleColor)Enum.Parse(typeof(ConsoleColor), ColorOne);
ConsoleColor valuecolortwo = (ConsoleColor)Enum.Parse(typeof(ConsoleColor), ColorTwo);
try
{
foreach (string f in Directory.GetFiles(dir, filename))
{
StreamReader file = new StreamReader(f);
bool t = true;
int counter = 1;
while ((fileline = file.ReadLine()) != null)
{
if (fileline.Contains(word))
{
if (t)
{
t = false;
filecounter++;
Console.ForegroundColor = valuecolorone;
Console.WriteLine(" ");
Console.WriteLine(f);
Console.ForegroundColor = valuecolortwo;
}
linecounter++;
Console.WriteLine(counter.ToString() + ". " + fileline);
}
counter++;
}
file.Close();
file = null;
}
foreach (string d in Directory.GetDirectories(dir))
{
//Console.WriteLine(d);
DirSearch(d,word,filename);
}
}
catch (System.Exception ex)
{
Console.WriteLine(ex.Message);
}
}
}
}

If you want to speed up your code run a performance analysis and see what is taking the most time. I can almost guaruntee the longest step here will be
fileline.Contains(word)
This function is called on every line of the file, on every file. Naively searching for a word in a string can taken len(string) * len(word) comparisons.
You could code your own Contains method, that uses a faster string comparison algorithm. Google for "fast string exact matching". You could try using a regex and seeing if that gives you a performance enhancement. But I think the simplest optimization you can try is :
Don't read every line. Make a large string of all the content of the file.
StreamReader streamReader = new StreamReader(filePath, Encoding.UTF8);
string text = streamReader.ReadToEnd();
Run contains on this.
If you need all the matches in a file, then you need to use something like Regex.Matches(string,string).
After you have used regex to get all the matches for a single file, you can iterate over this match collection (if there are any matches). For each match, you can recover the line of the original file by writing a function that reads forward and backward from the match object index attribute, to where you find the '\n' character. Then output that string between those two newlines, to get your line.
This will be much faster, I guarantee it.
If you want to go even further, some things I've noticed are :
Remove the try catch statement from outside the loop. Only use it exactly where you need it. I would not use it at all.
Also make sure your system is running, ngen. Most setups usually have this, but sometimes ngen is not running. You can see the process in process explorer. Ngen generates a native image of the C# managed bytecode so the code does not have to be interpreted each time, but can be run natively. This speeds up C# a lot.
EDIT
Other points:
Why is there a difference between first and subsequent run times? Seems like caching. The OS could have cached the requests for the directories, for the files, for running and loading programs. Usually one sees speedups after a first run. Ngen could also be playing a part here, too, in generating the native image after compilation on the first run, then storing that in the native image cache.
In general, I find C# performance too variable for my liking. If the optimizations suggested are not satisfactory and you want more consistent performance results, try another language -- one that is not 'managed'. C is probably the best for your needs.

.Net library to move / copy a file while preserving timestamps

Does anyone know of a .Net library where a file can be copied / pasted or moved without changing any of the timestamps. The functionality I am looking for is contained in a program called robocopy.exe, but I would like this functionality without having to share that binary.
Thoughts?

public static void CopyFileExactly(string copyFromPath, string copyToPath)
{
var origin = new FileInfo(copyFromPath);
origin.CopyTo(copyToPath, true);
var destination = new FileInfo(copyToPath);
destination.CreationTime = origin.CreationTime;
destination.LastWriteTime = origin.LastWriteTime;
destination.LastAccessTime = origin.LastAccessTime;
}

When executing without administrative privileges Roy's answer will throw an exception (UnauthorizedAccessException) when attempting to overwrite existing read only files or when attempting to set the timestamps on copied read only files.
The following solution is based on Roy's answer but extends it to overwrite read only files and to change the timestamps on copied read only files while preserving the read only attribute of the file all while still executing without admin privilege.
public static void CopyFileExactly(string copyFromPath, string copyToPath)
{
if (File.Exists(copyToPath))
{
var target = new FileInfo(copyToPath);
if (target.IsReadOnly)
target.IsReadOnly = false;
}
var origin = new FileInfo(copyFromPath);
origin.CopyTo(copyToPath, true);
var destination = new FileInfo(copyToPath);
if (destination.IsReadOnly)
{
destination.IsReadOnly = false;
destination.CreationTime = origin.CreationTime;
destination.LastWriteTime = origin.LastWriteTime;
destination.LastAccessTime = origin.LastAccessTime;
destination.IsReadOnly = true;
}
else
{
destination.CreationTime = origin.CreationTime;
destination.LastWriteTime = origin.LastWriteTime;
destination.LastAccessTime = origin.LastAccessTime;
}
}

You can read and write all the timestamps there are, using the FileInfo class:
CreationTime
LastAccessTime
LastWriteTime

You should be able to read the values you need, make whatever changes you wish and then restore the previous values by using the properties of FileInfo.

How to set a dynamic number of threadCounter variables?

I'm not really into multithreading so probably the question is stupid but it seems I cannot find a way to solve this problem (especially because I'm using C# and I've been using it for a month).
I have a dynamic number of directories (I got it from a query in the DB). Inside those queries there are a certain amount of files.
For each directory I need to use a method to transfer these files using FTP in a cuncurrent way because I have basically no limit in FTP max connections (not my word, it's written in the specifics).
But I still need to control the max amount of files transfered per directory. So I need to count the files I'm transfering (increment/decrement).
How could I do it? Should I use something like an array and use the Monitor class?
Edit: Framework 3.5

You can use the Semaphore class to throttle the number of concurrent files per directory. You would probably want to have one semaphore per directory so that the number of FTP uploads per directory can be controlled independently.
public class Example
{
public void ProcessAllFilesAsync()
{
var semaphores = new Dictionary<string, Semaphore>();
foreach (string filePath in GetFiles())
{
string filePathCapture = filePath; // Needed to perform the closure correctly.
string directoryPath = Path.GetDirectoryName(filePath);
if (!semaphores.ContainsKey(directoryPath))
{
int allowed = NUM_OF_CONCURRENT_OPERATIONS;
semaphores.Add(directoryPath, new Semaphore(allowed, allowed));
}
var semaphore = semaphores[directoryPath];
ThreadPool.QueueUserWorkItem(
(state) =>
{
semaphore.WaitOne();
try
{
DoFtpOperation(filePathCapture);
}
finally
{
semaphore.Release();
}
}, null);
}
}
}

var allDirectories = db.GetAllDirectories();
foreach(var directoryPath in allDirectories)
{
DirectoryInfo directories = new DirectoryInfo(directoryPath);
//Loop through every file in that Directory
foreach(var fileInDir in directories.GetFiles()) {
//Check if we have reached our max limit
if (numberFTPConnections == MAXFTPCONNECTIONS){
Thread.Sleep(1000);
}
//code to copy to FTP
//This can be Aync, when then transfer is completed
//decrement the numberFTPConnections so then next file can be transfered.
}
}
You can try something along the lines above. Note that It's just the basic logic and there are proberly better ways to do this.