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Read text from a text file with specific pattern

Hi there I have a requirement where i need to read content from a text file. The sample text content is as below.
Name=Check_Amt
Public=Yes
DateName=pp
Name=DBO
I need to read the text and only extract the value which comes after Name='What ever text'.
So I am expecting the output as Check_Amt, DBO
I need to do this in C#

When querying data (e.g. file lines) Linq is often a convenient tool; if the file has lines in
name=value
format, you can query it like this
Read file lines
Split each line into name, value pair
Filter pairs by their names
Extract value from each pair
Materialize values into a collection
Code:
using System.Linq;
...
// string[] {"Check_Amt", "DBO"}
var values = File
.ReadLines(#"c:\MyFile.txt")
.Select(line => line.Split(new char[] { '=' }, 2)) // split into name, value pairs
.Where(items => items.Length == 2) // to be on the safe side
.Where(items => items[0] == "Name") // name == "Name" only
.Select(items => items[1]) // value from name=value
.ToArray(); // let's have an array
finally, if you want comma separated string, Join the values:
// "Check_Amt,DBO"
string result = string.Join(",", values);

Another way:
var str = #"Name=Check_Amt
Public=Yes
DateName=pp
Name=DBO";
var find = "Name=";
var result = new List<string>();
using (var reader = new StringReader(str)) //Change to StreamReader to read from file
{
string line;
while ((line = reader.ReadLine()) != null)
{
if (line.StartsWith(find))
result.Add(line.Substring(find.Length));
}
}

You can use LINQ to select what you need:
var names=File. ReadLines("my file.txt" ).Select(l=>l.Split('=')).Where(t=>t.Length==2).Where(t=>t[0]=="Name").Select(t=>t[1])

I think that the best case would be a regex.
using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = #"(?<=Name=).*?(?=Public)";
string input = #"Name=Check_Amt Public=Yes DateName=pp Name=DBO";
RegexOptions options = RegexOptions.Multiline;
foreach (Match m in Regex.Matches(input, pattern, options))
{
Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index);
}
}
}
EDIT: My answer was written before your question were corrected, while it's still working the LINQ answer would be better IMHO.

Extract a pattern from a group of filenames and place into listbox

I have a folder with a lot of files like this:
2016-01-02-03-abc.txt
2017-01-02-03-defjh.jpg
2018-05-04-03-hij.txt
2022-05-04-03-klmnop.jpg
I need to extract the pattern from each group of filenames.
For example, I need the pattern 01-02-03 from the first two files placed in a list. I also need the pattern 05-04-03 placed in the same list. So, my list will look like this:
01-02-03
05-04-03
Here is what I have so far. I can successfully remove the characters but getting one instance of a pattern back into a list is beyond my pay grade:
public void GetPatternsToList()
{
//Get all filenames with characters removed and place in listbox.
List<string> files = new List<string>(Directory.EnumerateFiles(folderBrowserDialog1.SelectedPath));
foreach (var file in files)
{
var removeallbeforefirstdash = file.Substring(file.IndexOf("-") + 1); // removes everthing before the dash in the filename
var finalfile = removeallbeforefirstdash.Substring(0,removeallbeforefirstdash.LastIndexOf("-")); // removes everything after dash in name -- will crash if file without dash is in folder (not sure how to fix this either)
string[] array = finalfile.ToArray(); // I need to do the above with each file in the list and then place it back in an array to display in a listbox
List<string> filesList = array.ToList();
listBox1.DataSource = filesList;
}
}

You could do it this way:
public void GetPatternsToList()
{
var files = Directory.GetFiles(folderBrowserDialog1.SelectedPath);
var patterns = new HashSet<string>();
foreach (var file in files)
{
var splitFileName = file.Split('-').Skip(1).Take(3);
var joinedFileName = string.Join("-", splitFileName);
if(!string.IsNullOrEmpty(joinedFileName)
patterns.Add(joinedFileName);
}
listBox1.DataSource = patterns;
}
I used a HashSet<string> in order to avoid adding duplicate patterns to the DataSource.
A few remarks that aren't related to your question, but your code in general:
I would pass the SelectedPath as a string to the method
I would let the method return you the HashSet
If you implement the above, please also name the method accordingly
All of the above is of course optional for you, but would improve your code quality.

Try this:
public void GetPatternsToList()
{
List<string> files = new List<string>(Directory.EnumerateFiles(folderBrowserDialog1.SelectedPath));
List<string> resultFiles = new List<string>();
foreach (var file in files)
{
var removeallbeforefirstdash = file.Substring(file.IndexOf("-") + 1); // removes everthing before the dash in the filename
var finalfile = removeallbeforefirstdash.Substring(0, removeallbeforefirstdash.LastIndexOf("-")); // removes everything after dash in name -- will crash if file without dash is in folder (not sure how to fix this either)
resultFiles.Add(finalfile);
}
listBox1.DataSource = resultFiles.Distinct().ToList();
}

Split does not work as expected with commas

I need to write a CSV Parser I am now trying to separat the fields to manipulate them.
Sample CSV:
mitarbeiter^tagesdatum^lohnart^kostenstelle^kostentraeger^menge^betrag^belegnummer
11005^23.01.2018^1^^31810020^5,00^^
11081^23.01.2018^1^^31810020^5,00^^
As you can see, there a several empty cells.
I am doing the following:
using (CsvFileReader reader = new CsvFileReader(path))
{
CsvRow row = new CsvRow();
while (reader.ReadRow(row))
{
foreach (string s in row)
{
csvROW.Add(new aCSVROW());
string[] items = s.Split(new char[] { '^' }, StringSplitOptions.None);
csvROW[0].mitarbeiter = items[0];
csvROW[0].tagesdatum = items[1];
csvROW[0].lohnart = items[2];
csvROW[0].kostenstelle = items[3];
csvROW[0].kostentraeger = items[4];
csvROW[0].menge = items[5];
csvROW[0].betrag = items[6];
csvROW[0].belegnummer = items[7];
}
}
}
Problem:
It seems that Split stops after the comma (5,00). The separator is ^ ... is there a reason why?
I tried several things without success...
Thank you so much!

CsvFileReader reads rows from a CSV file and then strings within that row. What else do you expect the CsvFileReader to do than separating the row?
After reading the second line, row will have the contents
11005^23.01.2018^1^^31810020^5
and
00^^
When you split the first row by ^, the last entry of the resulting array will be "5". Anyway, your code will throw, because you are trying to access items exceeding the bounds of the array.
I don't know CsvFileReader. Maybe you can pass ^ as a separator and spare the splitting of the string. Anyway, you could use a StreamReader, too. This will work much more like you expected.
using (StreamReader reader = new StreamReader(path))
{
while (!reader.EndOfStream)
{
var csvLine = reader.ReadLine();
csvROW.Add(new aCSVROW());
string[] items = csvLine.Split(new char[] { '^' }, StringSplitOptions.None);
csvROW[0].mitarbeiter = items[0];
csvROW[0].tagesdatum = items[1];
csvROW[0].lohnart = items[2];
csvROW[0].kostenstelle = items[3];
csvROW[0].kostentraeger = items[4];
csvROW[0].menge = items[5];
csvROW[0].betrag = items[6];
csvROW[0].belegnummer = items[7];
}
}

Is CsvRow meant to be the data of all rows, or of one row? Because as it is, you keep adding a new aCSVROW object into csvROW for each read line, but you keep replacing the data on just csvROW[0], the first inserted aCSVROW. This means that in the end, you will have a lot of rows that all have no data in them, except for the one on index 0, that had its properties overwritten on each iteration, and ends up containing the data of the last read row.
Also, despite using a CsvReader class, you are using plain normal String.Split to actually separate the fields. Surely that's what the CsvReader class is for?
Personally, I always use the TextFieldParser, from the Microsoft.VisualBasic.FileIO namespace. It has the advantage it's completely native in the .Net framework, and you can simply tell it which separator to use.
This function can get the data out of it as simple List<String[]>:
A:
Using C# to search a CSV file and pull the value in the column next to it
Once you have your data, you can paste it into objects however you want.
List<String[]> lines = SplitFile(path, textEncoding, "^");
// I assume "CsvRow" is some kind of container for multiple rows?
// Looks like pretty bad naming to me...
CsvRow allRows = new CsvRow();
foreach (String items in lines)
{
// Create new object, and add it to list.
aCSVROW row = new aCSVROW();
csvROW.Add(row);
// Fill the actual newly created object, not the first object in allRows.
// conside adding index checks here though to avoid index out of range exceptions.
row.mitarbeiter = items[0];
row.tagesdatum = items[1];
row.lohnart = items[2];
row.kostenstelle = items[3];
row.kostentraeger = items[4];
row.menge = items[5];
row.betrag = items[6];
row.belegnummer = items[7];
}
// Done. All rows added to allRows.

CsvRow row = new CsvRow();
while (reader.ReadRow(row))
{
foreach (string s in row)
{
csvROW.Add(new aCSVROW());
s.Split("^","");
csvROW[0].mitarbeiter = items[0];
csvROW[0].tagesdatum = items[1];
csvROW[0].lohnart = items[2];
csvROW[0].kostenstelle = items[3];
csvROW[0].kostentraeger = items[4];
csvROW[0].menge = items[5];
csvROW[0].betrag = items[6];
csvROW[0].belegnummer = items[7];
}
}
}

How to split a server address and store in a list

I have a List<string> with some 10 strings.
The values are as follows:
\\Server\Site\MySite\File1.xml
\\Server\Site\MySite\File2.xml
\\Server\Site\MySite\File2.xml
.......................
\\Server\Site\MySite\File10.xml
I need to extract \MySIte\File1.xml to \MySite\File10.xml and store in another list.
I tried to use Split keyword, with another list to populate the splitted string. But it doesn't seem to give the correct answer.
Below is the code:
for(int index=0;index<list.Count;list++)
{
string[] myArray=list[index].Split('\\');
for(int innerIndex=0;innerIndex<myArray.Length;innerIndex++)
{
anotherList[innerIndex]=myArray[2]+"\\"+myArray[3];
}
}
Experts please help.

You don't need to work too hard if you know the input of all the strings
str.Substring(str.IndexOf("\\MySite"))

One word: LINQ!
var results = (from x in source
let parts = x.Split('\\')
select String.Join("\\", parts.Skip(1)).ToArray();

You can use following code.
List<string> source = new List<string>();
source.Add(#"\\Server\Site\MySite\File1.xml");
source.Add(#"\\Server\Site\MySite\File2.xml");
source.Add(#"\\Server\Site\MySite\File2.xml");
source.Add(#"\\Server\Site\MySite\File10.xml");
foreach(string s in source)
{
string[] parts = s.Split(new string[]{ Path.DirectorySeparatorChar.ToString() },StringSplitOptions.RemoveEmptyEntries);
Console.WriteLine(parts[parts.Length - 1] + Path.DirectorySeparatorChar +
parts[parts.Length - 2]);
}

I would just remove anything before \MySite and get the rest:
Test data used:
List<string> source = new List<string>
{
#"\\Server\Site\MySite\File1.xml",
#"\\Server\Site\MySite\File2.xml",
#"\\Server\Site\MySite\File2.xml",
#"\\Server\Site\MySite\File10.xml",
};
query:
var result =
source
// Start removing at 0 and remove everything before '\MySite'
.Select(x => x.Remove(0, x.IndexOf("\\MySite")))
.ToList();

C# reading variables into static string from text file

I have seen several posts giving examples of how to read from text files, and examples on how to make a string 'public' (static or const), but I haven't been able to combine the two inside a 'function' in a way that is making sense to me.
I have a text file called 'MyConfig.txt'.
In that, I have 2 lines.
MyPathOne=C:\TestOne
MyPathTwo=C:\TestTwo
I want to be able to read that file when I start the form, making both MyPathOne and MyPathTwo accessible from anywhere inside the form, using something like this :
ReadConfig("MyConfig.txt");
the way I am trying to do that now, which is not working, is this :
public voice ReadConfig(string txtFile)
{
using (StreamReader sr = new StreamResder(txtFile))
{
string line;
while ((line = sr.ReadLine()) !=null)
{
var dict = File.ReadAllLines(txtFile)
.Select(l => l.Split(new[] { '=' }))
.ToDictionary( s => s[0].Trim(), s => s[1].Trim());
}
public const string MyPath1 = dic["MyPathOne"];
public const string MyPath2 = dic["MyPathTwo"];
}
}
The txt file will probably never grow over 5 or 6 lines, and I am not stuck on using StreamReader or dictionary.
As long as I can access the path variables by name from anywhere, and it doesn't add like 400 lines of code or something , then I am OK with doing whatever would be best, safest, fastest, easiest.
I have read many posts where people say the data should stored in XML, but I figure that part really doesn't matter so much because reading the file and getting the variables part would be almost the same either way. That aside, I would rather be able to use a plain txt file that somebody (end user) could edit without having to understand XML. (which means of course lots of checks for blank lines, does the path exist, etc...I am OK with doing that part, just wanna get this part working first).
I have read about different ways using ReadAllLines into an array, and some say to create a new separate 'class' file (which I don't really understand yet..but working on it). Mainly I want to find a 'stable' way to do this.
(project is using .Net4 and Linq by the way)
Thanks!!

The code you've provided doesn't even compile. Instead, you could try this:
public string MyPath1;
public string MyPath2;
public void ReadConfig(string txtFile)
{
using (StreamReader sr = new StreamReader(txtFile))
{
// Declare the dictionary outside the loop:
var dict = new Dictionary<string, string>();
// (This loop reads every line until EOF or the first blank line.)
string line;
while (!string.IsNullOrEmpty((line = sr.ReadLine())))
{
// Split each line around '=':
var tmp = line.Split(new[] { '=' },
StringSplitOptions.RemoveEmptyEntries);
// Add the key-value pair to the dictionary:
dict[tmp[0]] = dict[tmp[1]];
}
// Assign the values that you need:
MyPath1 = dict["MyPathOne"];
MyPath2 = dict["MyPathTwo"];
}
}
To take into account:
You can't declare public fields into methods.
You can't initialize const fields at run-time. Instead you provide a constant value for them at compilation time.

Got it. Thanks!
public static string Path1;
public static string Path2;
public static string Path3;
public void ReadConfig(string txtFile)
{
using (StreamReader sr = new StreamReader(txtFile))
{
var dict = new Dictionary<string, string>();
string line;
while (!string.IsNullOrEmpty((line = sr.ReadLine())))
{
dict = File.ReadAllLines(txtFile)
.Select(l => l.Split(new[] { '=' }))
.ToDictionary( s => s[0].Trim(), s => s[1].Trim());
}
Path1 = dict["PathOne"];
Path2 = dict["PathTwo"];
Path3 = Path1 + #"\Test";
}
}

You need to define the variables outside the function to make them accessible to other functions.
public string MyPath1; // (Put these at the top of the class.)
public string MyPath2;
public voice ReadConfig(string txtFile)
{
var dict = File.ReadAllLines(txtFile)
.Select(l => l.Split(new[] { '=' }))
.ToDictionary( s => s[0].Trim(), s => s[1].Trim()); // read the entire file into a dictionary.
MyPath1 = dict["MyPathOne"];
MyPath2 = dict["MyPathTwo"];
}

This question is similar to Get parameters out of text file
(I put an answer there. I "can't" paste it here.)
(Unsure whether I should "flag" this question as duplicate. "Flagging" "closes".)
(Do duplicate questions ever get consolidated? Each can have virtues in the wording of the [often lame] question or the [underreaching and overreaching] answers. A consolidated version could have the best of all, but consolidation is rarely trivial.)