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How to count strings from text file in C#

in this button click event I am trying to count strings from text file that are the same as in textboxes, then display number of them in label. My problem is that I have no idea how to count them-I'm talking about code inside if-statement. I would really appreciate any help.
private void btnCalculate_Click(object sender, EventArgs e)
{
string openFileName;
using (OpenFileDialog ofd = new OpenFileDialog())
{
if (ofd.ShowDialog() != DialogResult.OK)
{
MessageBox.Show("You did not select OK");
return;
}
openFileName = ofd.FileName;
}
FileStream fs = null;
StreamReader sr = null;
try
{
fs = new FileStream("x", FileMode.Open, FileAccess.Read);
fs.Seek(0, SeekOrigin.Begin);
sr = new StreamReader(fs);
string s = sr.ReadLine();
while (s != null)
{
s = sr.ReadLine();
}
if(s.Contains(tbFirstClub.Text))
{
s.Count = lblResult1.Text; //problem is here
}
else if(s.Contains(tbSecondClub.Text))
{
s.Count = lblResult2.Text; //problem is here
}
}
catch (IOException)
{
MessageBox.Show("Error reading file");
}
catch (Exception)
{
MessageBox.Show("Something went wrong");
}
finally
{
if (sr != null)
{
sr.Close();
}
}
}
Thanks in advance.

s.Count = lblResult1.Text; //problem is here
wait...you are saying here..
you have a variable (s)
and you access its property (Count)
and then set it to the label text(lblResult1.Text)
is that what you're trying to do? because the reverse seems more likely

Using LINQ you can get the number of occurences, like below:
int numOfOcuurences= s.Count( s=> s == tbFirstClub.Text);
lblResult1.Text = numOfOcuurences.ToString();

welcome to Stack Overflow.
I want to point out something you said.
else if(s.Contains(tbSecondClub.Text))
{
s.Count = lblResult2.Text; //problem is here
}
S is our string that we just read from the file.
You're saying assoung S.Count (The length of the string) to text.
I don't think this is what you want. We want to return the number of times specified strings show up in a specified file
Let's refactor this, (And add some tricks along the way).
// Let's create a dictionary to store all of our desired texts, and the counts.
var textAndCounts = new Dictionary<string, int>();
textAndCounts.Add(tbFirstClub.Text, 0); // Assuming the type of Text is string, change acccorrdingly
textAndCounts.Add(tbSecondClub.Text, 0);
//We added both out texts fields to our dictionary with a value of 0
// Read all the lines from the file.
var allLines = File.ReadAllLines(openFileName); /* using System.IO */
foreach(var line in allLines)
{
if(line.Contains(tbFirstClub.Text))
{
textAndCounts[tbFirstClub.Text] += 1; // Go to where we stored our count for our text and increment
}
if(line.Contains(tbSecondClub.Text))
{
textandCounts[tbSecondClub.Text] += 1;
}
}
This should solve your problem, but it's still pretty brittle. Optimally, we want to design a system that works for any number of strings and counts them.
So how would I do it?
public Dictionary<string, int> GetCountsPerStringInFile(IEnumerable<string> textsToSearch, string filePath)
{
//Lets use Linq to create a dictionary, assuming all strings are unique.
//This means, create a dictionary in this list, where the key is the values in the list, and the value is 0 <Text, 0>
var textsAndCount = textsToSearch.ToDictionary(text => text, count => 0);
var allLines = File.ReadAllLines(openFileName);
foreach (var line in allLines)
{
// You didn't specify if a line could maintain multiple values, so let's handle that here.
var keysContained = textsAndCounts.Keys.Where(c => line.Contains(c)); // take all the keys where the line has that key.
foreach (var key in keysContained)
{
textsAndCounts[key] += 1; // increment the count associated with that string.
}
}
return textsAndCounts;
}
The above code allows us to return a data structure with any amount of strings with a count.
I think this is a good example for you to save you some headaches going forward, and it's probably a good first toe-dip into design patterns. I'd suggest looking up some material on Data structures and their use cases.

C# Finding the mean of every xth value in a file using streamreader

I'm relatively new to c# and I am trying to write a program that finds the mean of every xth value in a file using Streamreader. (For example if I wanted to find the mean of every fifth value in that file)
I written some code that reads the file and splits it into a new line for each comma, and this works fine, when I try and read each specific value.
However I'm struggling to think of a way to find every specific value, such as every 4th one and then find the mean of these and output it in the same program.
static void Main(string[] args)
{
using (var reader = new StreamReader(#"file"))
{
List<string> list = new List<string>();
while (!reader.EndOfStream)
{
var line = reader.ReadLine();
var values = line.Split(',');
list.Add(values[0]);
}
}
}
Any suggestions or help would be greatly appreciated

Try like this;
static void Main()
{
using (var reader = new StreamReader(#"file"))
{
int lineNumber = 4;
bool streamEnded = false;
List<string> list = new List<string>();
while (!streamEnded)
{
var line = ReadSpecificLine(reader, lineNumber,out streamEnded);
if (string.IsNullOrEmpty(line))
{
continue;
}
var values = line.Split(',');
list.Add(values[0]);
}
}
}
public static string ReadSpecificLine(StreamReader sr, int lineNumber,out bool streamEnded)
{
streamEnded = false;
for (int i = 1; i < lineNumber; i++)
{
if (sr.EndOfStream)
{
streamEnded = true;
return "";
}
sr.ReadLine();
}
if (sr.EndOfStream)
{
streamEnded = true;
return "";
}
return sr.ReadLine();
}

StreamReader read last line that contains

I am trying to read from a text file that has multiple outputs from when writing to it but when I want to read from the textfile that I already outputted stuff to, I want to choose the last entry(bear in mind each entry when writing has 5 lines and I just want the line containing "Ciphered text:")
But with this it is reading the lines containing that but I cannot work how to make it show only the last entry containing the string I specified.
using System;
using System.IO;
namespace ReadLastContain
{
class StreamRead
{
static void Main(string[] args)
{
string TempFile = #"C:\Users\Josh\Desktop\text2.txt";
using (var source = new StreamReader(TempFile))
{
string line;
while ((line = source.ReadLine()) != null)
{
if (line.Contains("Ciphered Text:"))
{
Console.WriteLine(line);
}
}
}
}
}
}

I would suggest to use LINQ for better readability:
string lastCipheredText = File.ReadLines(TempFile)
.LastOrDefault(l => l.Contains("Ciphered Text:"));
it is null if there was no such line. If you can't use LINQ:
string lastCipheredText = null;
while ((line = source.ReadLine()) != null)
{
if (line.Contains("Ciphered Text:"))
{
lastCipheredText = line;
}
}
It will be overwritten always, so you automatically get the last line that contained it.

You can use Linq:
var text = File
.ReadLines(#"C:\Users\Josh\Desktop\text2.txt")
.LastOrDefault(line => line.Contains("Ciphered Text:"));
if (null != text) // if there´s a text to print out
Console.WriteLine(text);

Ignore certain lines in a text file (C# Streamreader)

I'm trying to work out a way of removing records from a program I'm writing. I have a text file with all the customer data spread over a set of lines and I read in these lines one at a time and store them in a List
When writing I simply append to the file. However, for deleting I had the idea of adding a character such as * or # to the front of lines no longer needed. However I am unsure how to do this
Below is how I currrently read the data in:
Thanks in advance
StreamReader dataIn = null;
CustomerClass holdcus; //holdcus and holdacc are used as "holding pens" for the next customer/account
Accounts holdacc;
bool moreData = false;
string[] cusdata = new string[13]; //holds customer data
string[] accdata = new string[8]; //holds account data
if (fileIntegCheck(inputDataFile, ref dataIn))
{
moreData = getCustomer(dataIn, cusdata);
while (moreData == true)
{
holdcus = new CustomerClass(cusdata[0], cusdata[1], cusdata[2], cusdata[3], cusdata[4], cusdata[5], cusdata[6], cusdata[7], cusdata[8], cusdata[9], cusdata[10], cusdata[11], cusdata[12]);
customers.Add(holdcus);
int x = Convert.ToInt32(cusdata[12]);
for (int i = 0; i < x; i++) //Takes the ID number for the last customer, as uses it to set the first value of the following accounts
{ //this is done as a key to which accounts map to which customers
moreData = getAccount(dataIn, accdata);
accdata[0] = cusdata[0];
holdacc = new Accounts(accdata[0], accdata[1], accdata[2], accdata[3], accdata[4], accdata[5], accdata[6], accdata[7]);
accounts.Add(holdacc);
}
moreData = getCustomer(dataIn, cusdata);
}
}
if (moreData != null) dataIn.Close();

Since your using string arrays, you can just do cusdata[index] = "#"+cusdata[index] to append it to the beginning of the line. However if your question is how to delete it from the file, why not skip the above step and just not add the line you want deleted when writing the file?

Here is a small read / write sample that should suit your needs. If it doesnt then let me know in the comment.
class Program
{
static readonly string filePath = "c:\\test.txt";
static void Main(string[] args)
{
// Read your file
List<string> lines = ReadLines();
//Create your remove logic here ..
lines = lines.Where(x => x.Contains("Julia Roberts") != true).ToList();
// Rewrite the file
WriteLines(lines);
}
static List<string> ReadLines()
{
List<string> lines = new List<string>();
using (StreamReader sr = new StreamReader(new FileStream(filePath, FileMode.Open)))
{
while (!sr.EndOfStream)
{
string buffer = sr.ReadLine();
lines.Add(buffer);
// Just to show you the results
Console.WriteLine(buffer);
}
}
return lines;
}
static void WriteLines(List<string> lines)
{
using (StreamWriter sw = new StreamWriter(new FileStream(filePath, FileMode.Create)))
{
foreach (var line in lines)
{
sw.WriteLine(line);
}
}
}
}
I used the following "data sample" for this
Matt Damon 100 222
Julia Roberts 125 152
Robert Downey Jr. 150 402
Tom Hanks 55 932

C#: read text file separated by additional newline character

I have some sql commands that are separated by an additional newline character:
ALTER TABLE XXX
ALTER COLUMN xxx real
ALTER TABLE YYY
ALTER COLUMN yyy real
ALTER TABLE ZZZ
ALTER COLUMN zzz real
I've tried reading the file by using an array of character separators such as the following,
new char[] { '\n', '\r'}
inside this method:
private static List<string> ReadFile(string FileName, char[] seps)
{
if (!File.Exists(FileName))
{
Console.WriteLine("File not found");
return null;
}
using (StreamReader sr = new StreamReader(FileName, Encoding.Default))
{
string content = sr.ReadToEnd();
return content.Split(seps, StringSplitOptions.RemoveEmptyEntries).ToList();
}
}
However, this doesn't seem to be working. I would like to have each command represented by a separate string. How can I do this?

Why not use File.ReadAllLines()?
private static List<string> ReadFile(string FileName)
{
if (!File.Exists(FileName))
{
Console.WriteLine("File not found");
return null;
}
var lines = File.ReadAllLines(FileName);
return lines.ToList();
}
This will automatically read and split your file by newlines.
If you want to filter out empty lines, do this:
var nonEmpty = ReadFile(path).Where(x => !string.IsNullOrEmpty(x)).ToList();
Side note, I would change your if statement to throw an exception if the file cannot be found.
if (!File.Exists(FileName))
{
throw new FileNotFoundException("Can't find file");
}

You can filter the examples. When I read them in, the empty lines had a length 1 and its char value said 131 for some reason. So I just filtered by length > 1
void Main()
{
var results = ReadFile(#"C:\temp\sql.txt", new char[]{'\n'});
Console.WriteLine(results.Count);
foreach (var result in results)
{
Console.WriteLine(result);
}
}
private static List<string> ReadFile(string FileName, char[] seps)
{
if (!File.Exists(FileName))
{
Console.WriteLine("File not found");
return null;
}
using (StreamReader sr = new StreamReader(FileName, Encoding.Default))
{
string content = sr.ReadToEnd();
return content.Split(seps, StringSplitOptions.RemoveEmptyEntries).Where (c => c.Length > 1).ToList();
}
}

Try This:
private static List<string> ReadFile(string FileName)
{
List<string> commands = new List<string>();
StringBuilder command = new StringBuilder();
if (!File.Exists(FileName))
{
Console.WriteLine("File not found");
return null;
}
foreach (var line in File.ReadLines(FileName))
{
if (!String.IsNullOrEmpty(line))
{
command.Append(line + "\n");
}
else
{
commands.Add(command.ToString());
command.Clear();
}
}
commands.Add(command.ToString());
return commands;
}

If you are sure you'll always have \r\n line endings, you can use:
var commands = content.Split(new []{"\r\n\r\n"}, StringSplitOptions.RemoveEmptyEntries);
Otherwise, try using regex:
var commands = Regex.Split(content, #"\r?\n\r?\n")

Thank you everyone for your answers. I ended up going with this helper method:
private static List<string> GetCommands(string location)
{
List<string> ret = new List<string>();
List<string> tmp = ReadFile(location, new string[] { "\r\n\r\n"});
for (int i = 0; i < tmp.Count; i++)
{
string rem = tmp[i].Replace("\r", "");
ret.Add(rem);
}
return ret;
}
As an aside, the equivalent is so much easier in Python. For example, what I'm trying to do can be expressed in these three lines:
with open('commands.txt', 'r') as f:
content = f.read()
commands = [ command for command in content.split('\n\n') ]