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Why am i receiving a "The process cannot access the file because it is being used by another process."

Im trying to process a set of files, i have a given number of txt files, which im currently joining into 1 txt file to apply filters to. The creation of the 1 file from multiple works great. But i have 2 questions and 1 error i cant seem to get around.
1 - Im getting an error when i try to read the newly created file so i can apply the filters. "The process cannot access the file because it is being used by another process."
2 - Am i approaching this the correct or more efficient way? by that i mean can the reading and filtering be applied before creating the concatenated file? I mean i still need to create a new file, but it would be nice to be able to apply everything before creating so that the file is already cleaned and ready for use outside the application.
Here is the current code that is having the issue and the 1 commented line that was my other attempt at releasing the file
private DataTable processFileData(string fname, string locs2 = "0", string effDate = "0", string items = "0")
{
DataTable dt = new DataTable();
string fullPath = fname;
try
{
using (StreamReader sr = new StreamReader(File.OpenRead(fullPath)))
//using (StreamReader sr = new StreamReader(File.Open(fullPath,FileMode.Open,FileAccess.Read, FileShare.Read)))
{
while (!sr.EndOfStream)
{
string line = sr.ReadLine();
if (!String.IsNullOrWhiteSpace(line))
{
string[] headers = line.ToUpper().Split('|');
while (dt.Columns.Count < headers.Length)
{
dt.Columns.Add();
}
string[] rows = line.ToUpper().Split('|');
DataRow dr = dt.NewRow();
for (int i = 0; i < rows.Count(); i++)
{
dr[i] = rows[i];
}
dt.Rows.Add(dr);
}
}
//sr.Close();
sr.Dispose();
}
string cls = String.Format("Column6 NOT LIKE ('{0}')", String.Join("','", returnClass()));
dt.DefaultView.RowFilter = cls;
return dt;
}
catch (IOException ex)
{
Console.WriteLine(ex.Message);
return dt;
}
Here is the concatenation method:
private void Consolidate(string fileType)
{
string sourceFolder = #"H:\Merchant\Strategy\Signs\BACKUP TAG DATA\Wave 6\" + sfld;
string destinationFile = #"H:\Merchant\Strategy\Signs\BACKUP TAG DATA\Wave 6\" + sfld + #"\"+ sfld + #"_consolidation.txt";
// Specify wildcard search to match TXT files that will be combined
string[] filePaths = Directory.GetFiles(sourceFolder, fileType);
StreamWriter fileDest = new StreamWriter(destinationFile, true);
int i;
for (i = 0; i < filePaths.Length; i++)
{
string file = filePaths[i];
string[] lines = File.ReadAllLines(file);
if (i > 0)
{
lines = lines.Skip(1).ToArray(); // Skip header row for all but first file
}
foreach (string line in lines)
{
fileDest.WriteLine(line);
}
}
if (sfld == "CLR")
{
clrFilter(destinationFile);
}
if (sfld == "UPL")
{
uplFilter(destinationFile);
}
if (sfld == "HD")
{
hdFilter(destinationFile);
}
if (sfld == "PD")
{
pdFilter(destinationFile);
}
fileDest.Close();
fileDest.Dispose();
}
What im trying to accomplish is reading min(2 or 3 txt files and as much as 13 txt files) and applying some filtering. But im getting this error:
"The process cannot access the file because it is being used by another process."

You're disposing the stream reader with the following line
sr.Dispose();
Using a 'Using' statement will dispose after the stream goes out of context. So remove the Dispose line (if it wasn't clear below)

Read credentials in text file for program c#?

This is my program, and it work correctly if i put username and password :
try
{
var url = #"https://mail.google.com/mail/feed/atom";
var User = username;
var Pasw = password;
var encoded = TextToBase64(User + ":" + Pasw);
var myweb = HttpWebRequest.Create(url) as HttpWebRequest;
myweb.Method = "POST";
myweb.ContentLength = 0;
myweb.Headers.Add("Authorization", "Basic " + encoded);
var response = myweb.GetResponse();
var stream = response.GetResponseStream();
textBox1.Text += ("Connection established with" + User + Pasw);
}
catch (Exception ex)
{
textBox1.Text += ("Error connection. Original error: " + ex.Message);
now i want read string of texfile, split them and read username and password like this format: username:password . There is my code at the moment:
Stream myStream = null;
OpenFileDialog openFileDialog1 = new OpenFileDialog();
openFileDialog1.InitialDirectory = "c:\\";
openFileDialog1.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*";
openFileDialog1.FilterIndex = 2;
openFileDialog1.RestoreDirectory = true;
string file_name = "";
file_name = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments) + file_name;
if (openFileDialog1.ShowDialog() == DialogResult.OK)
{
try
{
if ((myStream = openFileDialog1.OpenFile()) != null)
{
using (StringReader reader = new StringReader(file_name))
{
// Loop over the lines in the string.
int count = 0;
string line;
while ((line = reader.ReadLine()) != null)
{
string[] data = line.Split(':');
string username = data[0].Trim();
string password = data[1].Trim();
count++;
/* Console.WriteLine("Line {0}: {1}", count, line); */
}
reader.Close();
}
}
}
catch (Exception ex)
{
MessageBox.Show("Error: Could not read file from disk. Original error: " + ex.Message);
}

You open the file selected by the user, but then try to read from a variable file_name that is not the name of a file but the name of a well kwown folder. Perhaps you want this
try
{
if (openFileDialog1.FileName != string.Empty)
{
using (StreamReader reader = new StreamReader(openFileDialog1.FileName))
{
....
}
}
}
In this same code you use a StringReader, but instead you need a StreamReader to read from a file. StringReader takes the value passed in its constructor and return in the ReadLine call. Then you split the line at the colon but of course this is not the content of your file.
There are other problems in your code. For example, what do you do with the username and password loaded from the line? They are declared as local variables and not used anywhere, so at the next loop they are overwritten and lost.
So, a UserData class could be a possible answer
public class UserData
{
public string UserName {get; set;}
public string Password {get; set;}
}
and declare at the form global level an
List<UserData> data = new List<UserData>
and in your loop
public void button1_Click(object sender, EventArgs e)
{
try
{
if (openFileDialog1.FileName != string.Empty)
{
using (StreamReader reader = new StreamReader(openFileDialog1.FileName))
{
int count = 0;
string line;
while ((line = reader.ReadLine()) != null)
{
UserData d = new UserData();
string[] parts = line.Split(':');
d.UserName = parts[0].Trim();
d.Password = parts[1].Trim();
data.Add(d);
}
// At the loop end you could use the List<UserData> like a normal array
foreach(UserData ud in data)
{
Console.WriteLine("User=" + dd.UserName + " with password=" + dd.Password);
}
}
}
}
}
public void button2_Click(object sender, EventArgs e)
{
try
{
if(data.Count() == 0)
{
MessageBox.Show("Load user info first");
return;
}
var url = #"https://mail.google.com/mail/feed/atom";
var encoded = TextToBase64(data[0].UserName + ":" + data[0].Password);
.....
A warning note. Of course this is just demo code. Remember that in a real scenario saving passwords in clear text is a big security concern. The impact of this is relative to the context of your application but should not be downplayed. A better course of action is to store an hashing of the password values and apply the same hashing function when you need to compare password

You are creating StringReader from file_name varialbe, which is (according to your code)
string file_name = "";
file_name = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments) + file_name;
and points to nothere.
Also you have stream created for file being selected with open file dialog but you haven't use this stream.

write and read from byte stream

I have a page where the User can either upload their own csv or enter values into a listbox which then creates a csv (in the background). Regardless of which way the csv gets created I need to upload that csv to our server via a byte stream.
My problem is that when Im creating the csv I shouldn't have to create a temporary file, I should be able to write to the stream then read it back for uploading. How can I remove the need for the temporary file?
current code which works (but uses temp file):
try {
string filename = DateTime.Now.ToString("MMddyyHmssf");
filename = filename + ".csv";
string directory = ConfigurationManager.AppSettings["TempDirectory"].ToString();
path = Path.Combine(directory, filename);
using (StreamWriter sw = File.CreateText(path)) {
foreach (ListItem item in this.lstAddEmailAddress.Items) {
sw.WriteLine(" , ," + item.ToString());
}
}
} catch (Exception ex) {
string error = "Cannot create temp csv file used for importing users by email address. Filepath: " + path + ". FileException: " + ex.ToString();
this.writeToLogs(error, 1338);
}
}
// put here for testing the byte array being sent vs ready byte[] byteArray = System.IO.File.ReadAllBytes(path);
myCsvFileStream = File.OpenRead(path);
nFileLen = (int)myCsvFileStream.Length;
I have tried
Stream myCsvFileStream;
using (StreamWriter sw = new StreamWriter(myCsvFileStream)) {
foreach (ListItem item in this.lstAddEmailAddress.Items) {
sw.WriteLine(" , ," + item.ToString());
}
}
However since myCsvFileStream is not initialized (because stream is a static class) it is always null.
Here is what I do with the data (byte stream) after creating the csv.
byte[] file = new byte[nFileLen];
myCsvFileStream.Read(file, 0, nFileLen);
bool response = this.repositoryService.SaveUsers(this.SelectedAccount.Id, file, this.authenticatedUser.SessionToken.SessionId);
myCsvFileStream.Close();
In the end I used StringBuilder to create my csv file contents. Then got a byte array of its contents and used that to populate my shared stream (I say shared because when the user enters their own CSV file it is a HttpPostedFile but when sending it to our server via the rest call (respositoryservices.saveusers) it uses the same byte stream that it would via this method)
StringBuilder csvFileString = new StringBuilder();
sharedStreamForBatchImport = new MemoryStream();
foreach (ListItem item in this.lstAddEmailAddress.Items) {
csvFileString.Append(",," + item.ToString() + "\\r\\n");
}
//get byte array of the string
byteArrayToBeSent = Encoding.ASCII.GetBytes(csvFileString.ToString());
//set length for read
byteArraySize = (int)csvFileString.Length;
//read bytes into the sharedStreamForBatchImport (byte array)
sharedStreamForBatchImport.Read(byteArrayToBeSent, 0, byteArraySize);

You want to create a new MemoryStream()

Here is a function I use to write CSV files
public static bool WriteCsvFile(string path, StringBuilder stringToWrite)
{
try
{
using (StreamWriter sw = new StreamWriter(path, false)) //false in ordre to overwrite the file if it already exists
{
sw.Write(stringToWrite);
return true;
}
}
catch (Exception)
{
return false;
}
}
stringToWrite is just a string that has been created that way :
public static bool WriteCsvFile(string path, DataTable myData)
{
if (myData == null)
return false;
//Information about the table we read
int nbRows = myData.Rows.Count;
int nbCol = myData.Columns.Count;
StringBuilder stringToWrite = new StringBuilder();
//We get the headers of the table
stringToWrite.Append(myData.Columns[0].ToString());
for (int i = 1; i < nbCol; ++i)
{
stringToWrite.Append(",");
stringToWrite.Append(myData.Columns[i].ToString());
}
stringToWrite.AppendLine();
//We read the rest of the table
for (int i = 0; i < nbRows; ++i)
{
stringToWrite.Append(myData.Rows[i][0].ToString());
for (int j = 1; j < nbCol; ++j)
{
stringToWrite.Append(",");
stringToWrite.Append(myData.Rows[i][j].ToString());
}
stringToWrite.AppendLine();
}
return WriteCsvFile(path, stringToWrite);
}

Logical error in writing data in a text file in one column

My Usecase is to read data from a textfile by browsing to the location of the file containing the data to be quoted.the data from the file is save in a list. i use arraylist to get the data and loop through the arraylist and concatenate each string then create output file to store the data in single column as demostrated below
Example of a string:
20050000
40223120
40006523
sample out put:
'20050000',
'40223120',
'40006523'
But my code is currently displaying the output in the format:
'20050000'20050000,
'40223120'20050000,
'40006523'40006523
Pls help.
public List<string> list()
{
List<string> Get_Receiptlist = new List<string>();
String ReceiptNo;
openFileDialog1.ShowDialog();
string name_of_Textfile = openFileDialog1.FileName;
try
{
StreamReader sr = new StreamReader(name_of_Textfile);
{
while ((ReceiptNo = sr.ReadLine()) != null)
{
Get_Receiptlist.Add(ReceiptNo);
} // end while
MessageBox.Show("Record saved in the Data list");// just for testing purpose.
}// end StreamReader
}
catch (Exception err)
{
MessageBox.Show("Cannot read data from file");
}
return Get_Receiptlist;
}
private void button2_Click(object sender, EventArgs e)
{
string single_quotation = "'";
string comma = ",";
string paths = #"C:\Users\sample\Desktop\FileStream\Output.txt";
if (!File.Exists(paths))
{
// Create a file to write to.
using (StreamWriter sw = File.CreateText(paths))
{
string[] receipt = list().ToArray();
foreach (string rec in receipt)
{
string quoted_receipt = single_quotation + rec + single_quotation + rec + comma;
sw.WriteLine(quoted_receipt);
sw.WriteLine(Environment.NewLine);
}//foreach
sw.Close();
MessageBox.Show("Finish processing File");
}//end using
}// end if
}

In your method button2_Click you have bad loop:
string[] receipt = list().ToArray();
foreach (string rec in receipt)
{
string quoted_receipt = single_quotation + rec + single_quotation + rec + comma;
sw.WriteLine(quoted_receipt);
sw.WriteLine(Environment.NewLine);
}//foreach
First I'm not even sure its Java ... but if it was Java, then I would replace this fragment with this:
List<String> values = list();
for (int i = 0; i < values.size(); i++)
{
String rec = values.get(i);
StringBuilder quoted_receipt = new StringBuilder();
if (i > 0)
{
// add comma only if the first iteration already passed
quoted_receipt.append(comma);
}
quoted_receipt.append(single_quotation).append(rec).append(single_quotation);
sw.WriteLine(quoted_receipt.toString());
sw.WriteLine(Environment.NewLine);
}

Rewriting a text file after reading it

i got a file that is store in my appliction directory, and he got some site list.
i dont have any problem reading it, but when i want to write to it, i get
System.ArgumentException: Stream is not writeable
this is how i accsess the file:
FileStream theTextFileStream = new FileStream(Environment.CurrentDirectory + "/fourmlinks.txt",FileMode.OpenOrCreate);
and this is the function that throw me the expection:
public static void WriteNewTextToFile(string text, FileStream theFile)
{
string fileText = GetAllTextFromFile(theFile);
ArrayList fileLIst = populateListFromText(fileText);
using (StreamWriter fileWriter = new StreamWriter(theFile))
{
fileWriter.Write(String.Empty);
for (int i = 0; i < fileLIst.Count; i++)
{
fileWriter.WriteLine(fileLIst[i].ToString());
}
}
}
the function read the old and new text and add it to an arry. then i clean the file from every thing, and rewriting it with the old and new data from the arry i made.
i dont know if that will help but here is the file proprites:
Build Action: None
Copy To Out Put Directory: Copy always
why i cant rewrite the file?
this is the function i use to read the file content:
public static string GetAllTextFromFile(FileStream theFile)
{
string fileText = "";
using (theFile)
{
using (StreamReader stream = new StreamReader(theFile))
{
string currentLine = "";
while ((currentLine = stream.ReadLine()) != null)
{
fileText += currentLine + "\n";
}
}
}
return fileText;
}

You have to use Read/Write file access as third parameter -
FileStream theTextFileStream = new FileStream(Environment.CurrentDirectory + "/fourmlinks.txt",FileMode.OpenOrCreate, FileAccess.ReadWrite
);
Important - Remove using(theFile) statement:
public static string GetAllTextFromFile(FileStream theFile)
{
string fileText = "";
using (StreamReader stream = new StreamReader(theFile))
{
string currentLine = "";
while ((currentLine = stream.ReadLine()) != null)
{
fileText += currentLine + "\n";
}
}
return fileText;
}
Do not use using construct in your case as it will close the underlying stream as in your case you have to manually open and close stream objects.
This will allow you to write in the file as well.
For more information refer following links -
FileStream Constructor
FileAccess Enumeration