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Output from the sheet without repetitions

I am having a problem with the output in datagridview. I have a list of values ​​(for example / 1/3/5) and I need to display the names of objects that have at least one match with one of the digits. However, some objects have several matches and because of this they are displayed more than once, this is what I need to fix.
To select each element that I need to search for, I use a foreach. And in order to select the elements that have already been displayed, I created two sheets. In pruv I put all the elements that come in, and in pruv2 I put elements that were not previously displayed. To compare the elements of these sheets, I wrote a for-loop. But at the moment the displayed objects are displayed several more times.
public static DataTable table = new DataTable();
public static DataTable tages = new DataTable();
**********************************************************************************************
DB.conetc();
table = new DataTable();
string sql = "SELECT history FROM users WHERE login= '" + nameuser + "';";
DB.usradapt(sql, 2);
string[] histor = table.Rows[0]["history"].ToString().Split('/');
List<string> pruv = new List<string>();
List<string> pruv2 = new List<string>();
pruv2.Add("0");
table = new DataTable();
foreach (var word in histor)
{
int count = 0;
sql = "SELECT NameFilm FROM films WHERE tags LIKE'" + $"%{word}%'";
DB.usradapt(sql, 3);
pruv.Add(tages.Rows[count]["NameFilm"].ToString());
for (int i = 0; i < pruv.Count; i++)
{
for (int j = 0; j < pruv2.Count; j++)
{
if (pruv[i] != pruv2[j])
{
pruv2.Add(pruv[i]);
DB.usradapt(sql, 2);
}
}
}
count++;
}
dgvResult.DataSource = table;
dataGridView1.DataSource = tages; //I display pruv content to understand what's inside
DB.connection.Close();
**********************************************************************************************
public class DB
{
public static SQLiteConnection connection = new SQLiteConnection();
public static void usradapt(string sql, int f)
{
SQLiteDataAdapter adapter = new SQLiteDataAdapter(sql, DB.connection);
if (f == 1) { adapter.Fill(FormLogin.table); }
else if (f == 2) { adapter.Fill(FormPage.table); }
else if (f == 3) { adapter.Fill(FormPage.tages); }
}
}
}
Users have a history that records tags when searching for a movie:
Each movie has its own tags:
The left screen table:
should display the names of films that have at least one of the story tags. In theory, they should be displayed as in the right table, but in such a way that the same movie does not appear multiple times

You can try writing ProductA and then calling it instead of "for"
public class ProductA : IEquatable<ProductA>
{
public string Name { get; set; }
public bool Equals(ProductA other)
{
if (other is null)
return false;
return this.Name == other.Name;
}
public override bool Equals(object obj) => Equals(obj as ProductA);
public override int GetHashCode() => (Name).GetHashCode();
}
for (int i = 0; i < pruv.Count; i++)
{
ProductA[] storeA = { new ProductA { Name = pruv[count] } };
ProductA[] storeB = { new ProductA { Name = pruv2[i] } };
bool equalAB = storeA.SequenceEqual(storeB);
if (!equalAB)
{
DB.usradapt(sql, 2);
pruv.Add(pruv2[i]);
}
}

Read lines of data from CSV then display data

I have to read info from a txt file, store it in a manner (array or list), then display the data. Program must include at least one additional class.
I've hit a wall and can't progress.
string, string, double, string
name,badge,salary,position
name,badge,salary,position
name,badge,salary,position
I'm sorry and I know the code below is disastrous but I'm at a loss and am running out of time.
namespace Employees
{
class Program
{
static void Main()
{
IndividualInfo collect = new IndividualInfo();
greeting();
collect.ReadInfo();
next();
for (int i = 0; i < 5; i++)
{
displayInfo(i);
}
exit();
void greeting()
{
Console.WriteLine("\nWelcome to the Software Development Company\n");
}
void next()
{
Console.WriteLine("\n*Press enter key to display information . . . *");
Console.Read();
}
void displayInfo(int i)
{
Console.WriteLine($"\nSoftware Developer {i + 1} Information:");
Console.WriteLine($"\nName:\t\t\t{collect.nameList[i]}");
}
void exit()
{
Console.WriteLine("\n\n*Press enter key to exit . . . *");
Console.Read();
Console.Read();
}
}
}
}
class IndividualInfo
{
public string Name { get; set; }
//public string Badge{ get; set; }
//public string Position{ get; set; }
//public string Salary{ get; set; }
public void ReadInfo()
{
int i = 0;
string inputLine;
string[] eachLine = new string[4];
string[,] info = new string[5, 4]; // 5 developers, 4x info each
StreamReader file = new StreamReader("data.txt");
while ((inputLine = file.ReadLine()) != null)
{
eachLine = inputLine.Split(',');
for (int x = 0; x < 5; x++)
{
eachLine[x] = info[i, x];
x++;
}
i++;
}
string name = info[i, 0];
string badge = info[i, 1];
string position = info[i, 2];
double salary = Double.Parse(info[i, 3]);
}
public List<string> nameList = new List<string>();
}
So far I think I can collect it with a two-dimensional array, but a List(s) would be better. Also, the code I've posted up there won't run because I can't yet figure out a way to get it to display. Which is why I'm here.

using System.IO;
static void Main(string[] args)
{
using(var reader = new StreamReader(#"C:\test.csv"))
{
List<string> listA = new List<string>();
List<string> listB = new List<string>();
while (!reader.EndOfStream)
{
var line = reader.ReadLine();
var values = line.Split(';');
listA.Add(values[0]);
listB.Add(values[1]);
}
}
}
https://www.rfc-editor.org/rfc/rfc4180
or
using Microsoft.VisualBasic.FileIO;
var path = #"C:\Person.csv"; // Habeeb, "Dubai Media City, Dubai"
using (TextFieldParser csvParser = new TextFieldParser(path))
{
csvParser.CommentTokens = new string[] { "#" };
csvParser.SetDelimiters(new string[] { "," });
csvParser.HasFieldsEnclosedInQuotes = true;
// Skip the row with the column names
csvParser.ReadLine();
while (!csvParser.EndOfData)
{
// Read current line fields, pointer moves to the next line.
string[] fields = csvParser.ReadFields();
string Name = fields[0];
string Address = fields[1];
}
}
http://codeskaters.blogspot.ae/2015/11/c-easiest-csv-parser-built-in-net.html
or
LINQ way:
var lines = File.ReadAllLines("test.txt").Select(a => a.Split(';'));
var csv = from line in lines
select (from piece in line
select piece);
^^Wrong - Edit by Nick
It appears the original answerer was attempting to populate csv with a 2 dimensional array - an array containing arrays. Each item in the first array contains an array representing that line number with each item in the nested array containing the data for that specific column.
var csv = from line in lines
select (line.Split(',')).ToArray();
This question was fully addressed here:
Reading CSV file and storing values into an array

Is there a code pattern for mapping a CSV with random column order to defined properties?

I have a CSV that is delivered to my application from various sources. The CSV will always have the same number columns and the header values for the columns will always be the same.
However, the columns may not always be in the same order.
Day 1 CSV may look like this
ID,FirstName,LastName,Email
1,Johh,Lennon,jlennon#applerecords.com
2,Paul,McCartney,macca#applerecords.com
Day 2 CSV may look like this
Email,FirstName,ID,LastName
resident1#friarpark.com,George,3,Harrison
ringo#allstarrband.com,Ringo,4,Starr
I want to read in the header row for each file and have a simple mechanism for associating each "column" of data with the associated property I have defined in my class.
I know I can use selection statements to figure it out, but that seems like a "bad" way to handle it.
Is there a simple way to map "columns" to properties using a dictionary or class at runtime?

Use a Dictionary to map column heading text to column position.
Hard-code mapping of column heading text to object property.
Example:
// Parse first line of text to add column heading strings and positions to your dictionary
...
// Parse data row into an array, indexed by column position
...
// Assign data to object properties
x.ID = row[myDictionary["ID"]];
x.FirstName = row[myDictionary["FirstName"]];
...

You dont need a design pattern for this purpose.
http://www.codeproject.com/Articles/9258/A-Fast-CSV-Reader
I have used this Reader, while it is pretty good, it has a functionality as row["firstname"] or row["id"] which you can parse and create your objects.

I have parsed both CSV files using Microsoft.VisualBasic.FileIO.TextFieldParser. I have populated DataTable after parsing both csv files:
DataTable dt;
private void button1_Click(object sender, EventArgs e)
{
dt = new DataTable();
ParseCSVFile("day1.csv");
ParseCSVFile("day2.csv");
dataGridView1.DataSource = dt;
}
private void ParseCSVFile(string sFileName)
{
var dIndex = new Dictionary<string, int>();
using (TextFieldParser csvReader = new TextFieldParser(sFileName))
{
csvReader.Delimiters = new string[] { "," };
var colFields = csvReader.ReadFields();
for (int i = 0; i < colFields.Length; i++)
{
string sColField = colFields[i];
if (sColField != string.Empty)
{
dIndex.Add(sColField, i);
if (!dt.Columns.Contains(sColField))
dt.Columns.Add(sColField);
}
}
while (!csvReader.EndOfData)
{
string[] fieldData = csvReader.ReadFields();
if (fieldData.Length > 0)
{
DataRow dr = dt.NewRow();
foreach (var kvp in dIndex)
{
int iVal = kvp.Value;
if (iVal < fieldData.Length)
dr[kvp.Key] = fieldData[iVal];
}
dt.Rows.Add(dr);
}
}
}
}
day1.csv and day2.csv as mentioned in the question.
Here is how output dataGridView1 look like:

Here is a simple generic method that will take a CSV file (broken into string[]) and create from it a list of objects. The assumption is that the object properties will have the same name as the headers. If this is not the case you might look into the DataMemberAttribute property and modify accordingly.
private static List<T> ProcessCSVFile<T>(string[] lines)
{
List<T> list = new List<T>();
Type type = typeof(T);
string[] headerArray = lines[0].Split(new char[] { ',' });
PropertyInfo[] properties = new PropertyInfo[headerArray.Length];
for (int prop = 0; prop < properties.Length; prop++)
{
properties[prop] = type.GetProperty(headerArray[prop]);
}
for (int count = 1; count < lines.Length; count++)
{
string[] valueArray = lines[count].Split(new char[] { ',' });
T t = Activator.CreateInstance<T>();
list.Add(t);
for (int value = 0; value < valueArray.Length; value++)
{
properties[value].SetValue(t, valueArray[value], null);
}
}
return list;
}
Now, in order to use it just pass your file formatted as an array of strings. Let's say the class you want to read into looks like this:
class Music
{
public string ID { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public string Email { get; set; }
}
So you can call this:
List<Music> newlist = ProcessCSVFile<Music>(list.ToArray());
...and everything gets done with one call.

Performance problems with Linq To CSV

I have found a library which connects csv-files with linq. I understood the principles and my code works well. But i have some problems with big csv files.
http://www.codeproject.com/Articles/25133/LINQ-to-CSV-library
Now i want to access specific single items from my _dataTable object. I get them like this:
public class CsvFile
{
private IEnumerable<DataRow> _dataTable = cc.Read<DataRow>(_filePath, _inputFileDescription);
public string GetItem(int row, int column)
{
return _dataTable.ElementAt<DataRow>(row).ElementAt<DataRowItem>(column).Value;
}
}
When i now call the method like this in a loop:
CsvFile file1 = new CsvFile("C:\\dev_csvcompare\\Master.csv", ';', true);
for(int i = 0; i < 10000; i++)
{
string dummy = file1.GetItem(1, i); //Does not make sense, my loop is a bit more complicated
}
it gets very slow, because the IEnumerable opens the stream every call.
In the documentation(link) under "Deferred Reading" they say i can access the ienumerable "_dataTable" with a foreach loop (this does work fine), but this is in my case no option because i want access to specific items in the csv.
Are there possibilities to keep the filestream open so that the performace increases?
EDIT (My code, maybe a lot of nosense, im not so experienced with .net, c# and oop):
public void Compare(int key1, int key2, int col1, int col2)
{
string lastKeyCol1 = null;
string lastKeyCol2 = null;
List<string> sortedKeyColFile1 = new List<string>();
List<string> sortedKeyColFile2 = new List<string>();
int file1counter = 0;
int file2counter = 0;
int cnt = 0;
sortedKeyColFile1 = _file1.GetCol(key1);
sortedKeyColFile1.Sort();
sortedKeyColFile2 = _file2.GetCol(key2);
sortedKeyColFile2.Sort();
while ((file1counter < sortedKeyColFile1.Count) || (file2counter < sortedKeyColFile2.Count))
{
_outputList.Add(new OutputValues(key1, key2, col1, col2));
//Keys are in both files
if (sortedKeyColFile1[file1counter] == sortedKeyColFile2[file2counter])
{
if (lastKeyCol1 == sortedKeyColFile1[file1counter])
{
//Keys are redundant
_outputList[cnt].RedundantKeyF1 = true;
}
if (lastKeyCol2 == sortedKeyColFile2[file2counter])
{
//Keys are redundant
_outputList[cnt].RedundantKeyF2 = true;
}
lastKeyCol1 = sortedKeyColFile1[file1counter];
lastKeyCol2 = sortedKeyColFile2[file2counter];
_outputList[cnt].ValF1 = _file1.GetItem(file1counter, col1);
_outputList[cnt].ValF2 = _file2.GetItem(file2counter, col2);
_outputList[cnt].LineNumF1 = file1counter;
_outputList[cnt].LineNumF2 = file2counter;
//compare the values (because keys do match at this place)
_outputList[cnt].CompareResult = CompareString(_file1.GetItem(file1counter, col1), _file2.GetItem(file2counter, col2));
if (file1counter < sortedKeyColFile1.Count)
{
file1counter++;
}
if (file2counter < sortedKeyColFile2.Count)
{
file2counter++;
}
}
//Key sortedKeyColFile2[file2counter] is not in file 1
else if (file2counter < sortedKeyColFile2.Count && 0 < (string.Compare(sortedKeyColFile1[file1counter], sortedKeyColFile2[file2counter])))
{
_outputList[cnt].LineNumF2 = file2counter;
if (lastKeyCol2 == sortedKeyColFile2[file2counter])
{
//Keys are redundant
_outputList[cnt].RedundantKeyF2 = true;
}
lastKeyCol2 = sortedKeyColFile2[file2counter];
file2counter++;
}
//Key sortedKeyColFile1[file1counter] is not in file 2
else if (file1counter < sortedKeyColFile1.Count)
{
_outputList[cnt].LineNumF1 = file1counter;
if (lastKeyCol1 == sortedKeyColFile1[file1counter])
{
//Keys are redundant
_outputList[cnt].RedundantKeyF1 = true;
}
lastKeyCol1 = sortedKeyColFile1[file1counter];
file1counter++;
}
cnt++;
}
}
//And here the important part of the csv-file class, maybe not so interesting
public class CsvFile
{
private string _filePath = null;
private char _separator = ',';
private bool _hasHeader = true;
private CsvContext _cc = null;
private CsvFileDescription _inputFileDescription = null;
private List<string> _headers = null;
private IEnumerable<DataRow> _dataTable = null;
/// <summary>
/// Constructor for a new CsvFile object.
/// The Constructor initiates the Object and read the values out of the File
/// </summary>
/// <param name="filePath">Full path of the csv-file</param>
/// <param name="separator">Seperator of the csv-file, eg: ';' or ',' or '\t'</param>
/// <param name="hasHeader">Is true if the first col of the csv-file contains a headers</param>
public CsvFile(string filePath, char separator, bool hasHeader = true)
{
//Throws an exception if something is wrong with the file
File.OpenRead(filePath);
_filePath = filePath;
_separator = separator;
_hasHeader = hasHeader;
_cc = new CsvContext();
_inputFileDescription = new CsvFileDescription
{
SeparatorChar = separator,
FirstLineHasColumnNames = hasHeader
};
_dataTable = _cc.Read<DataRow>(_filePath, _inputFileDescription);
if (hasHeader)
{
ParseHeaders();
}
}
public List<string> GetCol(int col)
{
List<string> column = new List<string>();
int cnt = 0;
foreach(DataRow x in _dataTable)
{
column.Add(x[col].Value);
cnt++;
}
return column;
}
private void ParseHeaders()
{
System.IO.StreamReader file = new System.IO.StreamReader(_filePath);
if (!file.EndOfStream)
{
//_headers = file.ReadLine().Split(_separator);
_headers = new List<string> (file.ReadLine().Split(_separator));
}
file.Close();
}
}

Try this:
public class CsvFile
{
private IEnumerable<DataRow> rows = cc.Read<DataRow>(_filePath, _inputFileDescription);
//...
public IEnumerable<DataRow> Rows { get { return rows; } }
}
And then:
CsvFile file1 = new CsvFile("C:\\dev_csvcompare\\Master.csv", ';', true);
foreach(DataRow row in file1.Rows)
{
string dummy = row[1];
}

WPF list filtering

I am new to WPF so this is probably an easy question. I have an app that reads some words from a csv file and stores them in a list of strings. What I am trying to do is parametise this list to show the most popular words in my list. So in my UI I want to have a text box which when I enter a number e.g. 5 would filter the original list leaving only the 5 most popular (frequent) words in the new list. Can anyone assist with this final step? Thanks -
public class VM
{
public VM()
{
Words = LoadWords(fileList);
}
public IEnumerable<string> Words { get; private set; }
string[] fileList = Directory.GetFiles(#"Z:\My Documents\", "*.csv");
private static IEnumerable<string> LoadWords(String[] fileList)
{
List<String> words = new List<String>();
//
if (fileList.Length == 1)
{
try
{
foreach (String line in File.ReadAllLines(fileList[0]))
{
string[] rows = line.Split(',');
words.AddRange(rows);
}
}
catch (Exception ex)
{
System.Windows.MessageBox.Show(ex.Message, "Problem!");
}
}
else
{
System.Windows.MessageBox.Show("Please ensure that you have ONE read file in the source folder.", "Problem!");
}
return words;
}
}

A LINQ query that groups by the word and orders by the count of that word descending should do it. Try this
private static IEnumerable<string> GetTopWords(int Count)
{
var popularWords = (from w in words
group w by w
into grp
orderby grp.Count() descending
select grp.Key).Take(Count).ToList();
return popularWords;
}

You could use CollectionViewSource.GetDefaultView(viewModel.Words), which returns ICollectionView.
ICollectionView exposes Filter property of type Predicate<object>, that you could involve for filtering.
So the common scenario looks like:
ViewModel exposes property PopularCount, that is binded to some textbox in View.
ViewModel listens for PopularCount property's changing.
When notification occured, model obtains ICollectionView for viewModel.Words collection and set up Filter property.
You could find working sample of Filter property usage here. If you get stuck with code, let me know.

Instead of reading all the words into the list and then sorting it based on the frequency, a cleaner approach would be to create a custom class MyWord that stores the word and the frequency. While reading the file, the frequency of the word can be incremented. The class can implement IComparable<T> to compare the words based on the frequency.
public class MyWord : IComparable<MyWord>
{
public MyWord(string word)
{
this.Word = word;
this.Frequency = 0;
}
public MyWord(string word, int frequency)
{
this.Word = word;
this.Frequency = frequency;
}
public string Word { get; private set;}
public int Frequency { get; private set;}
public void IncrementFrequency()
{
this.Frequency++;
}
public void DecrementFrequency()
{
this.Frequency--;
}
public int CompareTo(MyWord secondWord)
{
return this.Frequency.CompareTo(secondWord.Frequency);
}
}
The main class VM would have these members,
public IEnumerable<MyWord> Words { get; private set; }
private void ShowMostPopularWords(int numberOfWords)
{
SortMyWordsDescending();
listBox1.Items.Clear();
for (int i = 0; i < numberOfWords; i++ )
{
listBox1.Items.Add(this.Words.ElementAt(i).Word + "|" + this.Words.ElementAt(i).Frequency);
}
}
And the call to ShowMostPopularWords()
private void Button_Click(object sender, RoutedEventArgs e)
{
int numberOfWords;
if(Int32.TryParse(textBox1.Text, NumberStyles.Integer, CultureInfo.CurrentUICulture, out numberOfWords))
{
ShowMostPopularWords(numberOfWords);
}
}

I'm not sure if grouping and ordering of the 'words' list is what you want but if yes this could be a way of doing it:
int topN = 3;
List<string> topNWords = new List<string>();
string[] words = new string[] {
"word5",
"word1",
"word1",
"word1",
"word2",
"word2",
"word2",
"word3",
"word3",
"word4",
"word5",
"word6",
};
// [linq query][1]
var wordGroups = from s in words
group s by s into g
select new { Count = g.Count(), Word = g.Key };
for (int i = 0; i < Math.Min(topN, wordGroups.Count()); i++)
{
// (g) => g.Count is a [lambda expression][2]
// .OrderBy and Reverse are IEnumerable extension methods
var element = wordGroups.OrderBy((g) => g.Count).Reverse().ElementAt(i);
topNWords.Add(element.Count + " - " + element.Word);
}
Thsi could be made much shorter by using ordering in the linq select clause but I wished to introduce you to inline lambdas and ienumerable extensions too.
The short version could be:
topNWords = (from s in words
group s by s
into g
orderby g.Count() descending
select g.Key).Take(Math.Min(topN, g.Count()).ToList();