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How to create a Class List with different numbers of inputs in C#

I'm working on my first real c# project and I have faced a problem with my way of creating List based on a Class, which I have no idea how to solve.
I’m trying to write some code, which takes an input file (txt/csv) of multiple constructions with multiple layers, put it into my program, and later write the constructions into a new txt/csv file.
When having the same numbers of layers, it works fine. But when the constructions have different numbers of layers it causes trouble and I get a “System.IndexOutOfRangeException”.
My question is: Can I make the Class which I’m basing my List on, dynamic (I don’t know if it is the technical term), so it work with different numbers of inputs? Both when Adding the construction to the program and when I write it to a new file?
My code is:
class Program
{
static void Main(string[] args)
{
// Filepath for the input and output file
string filePathIn_constructions = #"C:\Library\Constructions.txt";
string filePathOut = #"C:\Library\EPlus_Inputfile.txt";
// Creating a list of constructions based on the class. The list is made from the file "filePathIn_constructions"
List<Construction> allConstructions = new List<Construction>();
List<string> lines_constructions = File.ReadAllLines(filePathIn_constructions).ToList(); // add it to a list
// Adding all the data from the fil to the variable "allConstructions"
foreach (var line in lines_constructions)
{
string[] entries = line.Split(',');
Construction newConstruction = new Construction();
newConstruction.EIndex = entries[0];
newConstruction.Name = entries[1];
newConstruction.Layer1 = entries[2];
newConstruction.Layer2 = entries[3];
newConstruction.Layer3 = entries[4];
newConstruction.Layer4 = entries[5];
newConstruction.Layer5 = entries[6];
allConstructions.Add(newConstruction); // Add it to our list of constructions
}
List<string> output = new List<string>();
foreach (var x in allConstructions) // Printing the new
{
output.Add($"{x.EIndex}, {x.Name}, {x.Layer1}, {x.Layer2}, {x.Layer3}, {x.Layer4}, {x.Layer5}");
}
File.WriteAllLines(txtFilePathOut, output);
}
}
My Class for the Constructions is
public class Construction
{
public string EIndex { get; set; }
public string Name { get; set; }
public string Layer1 { get; set; }
public string Layer2 { get; set; }
public string Layer3 { get; set; }
public string Layer4 { get; set; }
public string Layer5 { get; set; }
}
An example of a input/output file could be
Construction,ConcreteWall,Concrete;
Construction,Brickwall1,Birck,Isulation,Brick;
Construction,Brickwall2,Birck,AirGap,Isulation,Brick;
Construction,Wood/Concrete Wall,Wood,Isulation,Concrete,Gypson;
Construction,Wood Wall,Wood,AirGap,Gypson,Isulaiton,Gypson;
I hope someone can help. Thanks.
Edit: I have to be able to excess the construction Name seperatly, because i'm using it to do some sorting of the.

public class Construction
{
public string EIndex { get; set; }
public string Name { get; set; }
public List<string> Layers { get; set; } = new List<string>();
}
foreach (var line in lines_constructions)
{
string[] entries = line.Split(',');
Construction newConstruction = new Construction();
newConstruction.EIndex = entries[0];
newConstruction.Name = entries[1];
for (int i=2; i < entries.Length; i++) {
newConstruction.Layers.Add(entries[i]);
}
allConstructions.Add(newConstruction);
}
foreach(var x in allConstuctions) {
File.AppendAllText(output, $"{x.EIndex}, {x.Name}, {string.Join(", ", x.Layers)}");
}

It is because you are trying to reach a cell of an array that doesn't exist (documentation)
In your input/output file you have lines that have between 3 and 7 values, and you are building an array entries out of those values. This means that you will have arrays with between 3 and 7 cells
The problem is that right after creating those arrays you try to access on every array the cells 0, 1, 2... up to the 7th, even for arrays that have only 3 cells!
What you could do to fix this in a simple way is to add columns to have the same number of separator on each lines (you defined the separator of your lines as column with line.Split(',')). This way, every arrays that you will create will always have 7 cells, even if the value inside is null

C# manipulating data parsed from CSV

I'm creating a program to generate schematics based off of user input. This has to be done dynamically/by hand due to the sheer volume of different possibilities (6.8M, growing exponentially). Right now I'm working on importing some data via CSV.
Example data:
Type,TIN_pos,TIN_ID,Desc
Elect, 0, X, Manual Regulator
Elect, 0, A, Electronic Regulator
Import code:
List<TIN_Fields> values = File.ReadAllLines("C:\\Users\\User\\Desktop\\Visual Basic\\CSV_Test_1.csv")
.Skip(1)
.Select(v => TIN_Fields.FromCsv(v))
.ToList();
public class TIN_Fields
{
public string Type;
public int TIN_pos;
public string TIN_ID;
public string Desc;
public static TIN_Fields FromCsv(string csvLine)
{
string[] values = csvLine.Split(',');
TIN_Fields _Fields = new TIN_Fields();
_Fields.Type = Convert.ToString(values[0]);
_Fields.TIN_pos = Convert.ToInt16(values[1]);
_Fields.TIN_ID = Convert.ToString(values[2]);
_Fields.Desc = Convert.ToString(values[3]);
return _Fields;
}
}
Once that data is Imported, I need to do two things with it,
display the raw csv data in a ListView table, just so users can see if anything in the list needs updating.
be able to compare the items in the list to various characters in a 10-digit hexadecimal code, and spit out some results.
First and foremost, i need to run through the list that was created with the above code, make sure that:
TIN_pos value = 0
because that is the character position of the input box.
Then, with the remaining options, look for the character represented in the input in the TIN_ID field.
Once found, it should then output the Desc field.
Everywhere I have looked says to use foreach, but that requires the array name, which is the part that is confusing me. I've tried filling in basically all of the variables in the FromCSV Method and usually get an error that the class doesn't have a definition.
to hopefully clear up confusion with my explanation, here is the code I created that does the same thing, but with the CSV data hard coded into it, using switch cases and if statements.
public partial class Form1 : Form
{
public string Model_Chassis;
public string Model_Test_Type;
public int ChannelNumberVar => Convert.ToInt32(TextBox_TIN[2]);
public string Tester_Type_Selector;
public string TextBox_TIN
{
get { return TIN_Entry_TextBox.Text; }
set { TIN_Entry_TextBox.Text = value; }
}
public string Model_Data_D
{
get { return Model_Data.Text; }
set { Model_Data.Text = value; }
}
public Form1()
{
InitializeComponent();
}
//Method grabs TIN Box data and decodes it to model information.
public void Model_Select()
{
//Picks Model Chassis
switch (char.ToUpper(TextBox_TIN[0]))
{
case 'H':
{
Model_Chassis = Coding.Model1.description;
}
break;
default:
{
Model_Data_D = "INVALID TIN";
}
break;
}
//Picks Test Type
switch (char.ToUpper(TextBox_TIN[3]))
{
case '0':
{
Model_Test_Type = Test_Types.TT_PD.TT_tt;
}
break;
case '1':
{
Model_Test_Type = Test_Types.TT_PV.TT_tt;
}
break;
default:
{
Model_Test_Type = "";
}
break;
}
//Puts chassis and Test Type together
if (Model_Data_D.Equals("INVALID TIN"))
{
;
}
else if (char.ToUpper(TextBox_TIN[2]).Equals(Coding.Num_Chan_1_2.tin_id))
{
Model_Data_D = $"{Model_Chassis}-{Model_Test_Type}";
}
else
{
Model_Data_D = $"{Model_Chassis}-{TextBox_TIN[2]}{Model_Test_Type}";
}
}
public class Coding
{
public char tin_id;
public string description;
public Coding(char TIN_ID, string Desc)
{
tin_id = TIN_ID;
description = Desc;
}
public static Coding Model1 = new Coding('H', "Model1");
public static Coding Num_Chan_1_2 = new Coding('X', "Single Channel");
public static Coding Elect_Reg_F_1 = new Coding('X', "Manual Regulator");
}
}
INPUT:
HXX0X
OUTPUT
Model1-PD
Thanks in advance for the help!

You're asking quite a few questions, and providing a lot of extra details in here, but for this:
"First and foremost, i need to run through the list that was created with the above code, make sure that:
TIN_pos value = 0
because that is the character position of the input box."
(seeing as you say you need to do this 'first and foremost').
In your FromCsv method, check the value as you create the record, and throw an error if it is invalid. Like this:
public static TIN_Fields FromCsv(string csvLine)
{
string[] values = csvLine.Split(',');
TIN_Fields _Fields = new TIN_Fields();
_Fields.Type = Convert.ToString(values[0]);
_Fields.TIN_pos = Convert.ToInt16(values[1]);
if(_Fields.TIN_pos != 0){
throw new Exception("TIN_pos must be 0");
}
_Fields.TIN_ID = Convert.ToString(values[2]);
_Fields.Desc = Convert.ToString(values[3]);
return _Fields;
}

Assuming you've read in your CSV correctly, which it seems you have, then selecting the appropriate TIN from the list is a simple LINQ statement. The following code assumes that TIN IDs are unique and only a single character in length.
static void Main(string[] args)
{
string testCsv = #"C:\Users\User\Desktop\Visual Basic\CSV_Test_1.csv";
List<TIN_Fields> values = File.ReadAllLines(testCsv)
.Skip(1)
.Select(v => TIN_Fields.FromCsv(v))
.ToList();
// Simulates input received from form
string input = "HXX0X";
TIN_Fields selectedTIN = values.First(x => x.TIN_ID == Convert.ToString(input[0]));
// Insert the description as needed in your ouput.
string output = $"{ selectedTIN.Desc }-";
}
Hopefully that answers another part of the problem. The Convert.ToString() is required because the output of input[0] is a char.

Comma delimited class property assignment problem

I'm loading a comma delimited file into a list, no problems here. Except the last segment is separated by a semicolon of which I need to put into an array that has a property name. In this case Sequence and Rotation. The code below works except giving it a property name.
Any advice would be much appreciated. I've kept the code below to bare-bones to avoid clutter.
Example CSV File: Bar001,P02;90
class PartDetail
{
public string Description
{
get;
set;
}
public string[] BottomEdge
{
get;
set;
}
public class SpecificDetails << < I want to use this class to specify the property name. {
public string Sequence
{
get;
set;
}
public string Rotation
{
get;
set;
}
}
public PartDetail(string line)
{
string[] parts = line.Split(',');
this.Description = parts[0];
this.BottomEdge = parts[1].Split(';'); << It 's here where I am struggling.
}
}

I think this will do the trick
class PartDetail
{
....
//create an instance of your SpecificDetails class
SpecificDetails Details = new SpecificDetails();
...
public PartDetail(string line)
{
string[] parts = line.Split(',');
this.Description = parts[0];
this.BottomEdge = parts[1].Split(';');
//assign the value to the properties of the "Details" instance
this.Details.Sequence = this.BottomEdge[0];
this.Details.Rotation = this.BottomEdge[1];
}
}

Use line.Split(new char[]{ ',', ';'}) and just pick the last index of the returned array to be the closing segment of your logic.

Dot net has a built in CSV parser, so there is no need to roll your own (https://coding.abel.nu/2012/06/built-in-net-csv-parser/)
using (TextFieldParser parser = new TextFieldParser(path))
{
parser.CommentTokens = new string[] { "#" };
parser.SetDelimiters(new string[] { ";" });
parser.HasFieldsEnclosedInQuotes = true;
// Skip over header line.
parser.ReadLine();
while (!parser.EndOfData)
{
string[] fields = parser.ReadFields();
}
}
Once parsed, you are left with the semicolon problem, which can easily be solved with string.Split.

C# Use CSV headers for assigning values to different variables

I'm reading a CSV file and am basically trying to use the headers to determine the ordinal position of the values in the file, though the last part is giving me some trouble. The following is what I have so far:
private static IEnumerable<Cow> ReadCowStream(Stream source)
{
bool isHeader = true;
var cows = new List<Cow>();
using (var reader = new StreamReader(source))
{
while (!reader.EndOfStream)
{
var line = reader.ReadLine();
if (line != null)
{
var values = line.Split(',');
if (isHeader && values.Contains("Weight") && values.Contains("Age"))
{
isHeader = false;
}
else
{
cows.Add(new Cow(
weight: values[0],
age: values[1]));
}
}
}
}
return animals;
}
Example CSV:
Weight,Age
300,10
319,11
100,1
370,9
In this case the output would be a List<Cow> with the first entry having values "Weight": "300" and "Age": "10" obviously, but what if "Weight" and "Age" are reversed? Then I'll assign the wrong values to the wrong variables.
Basically, I want to use the headers for determining whether to put values[0] into weight or age etc., as I assume I can't be guaranteed which comes first in the CSV I'm reading.

Using a library like CsvHelper, the values can be extracted based on the header name rather than index.
private static IEnumerable<Cow> ReadCowStream(Stream source) {
var cows = new List<Cow>();
using (var reader = new StreamReader(source)) {
var csv = new CsvReader(reader);
csv.Read();
csv.ReadHeader();
while (csv.Read()) {
cows.Add(new Cow(weight: csv["Weight"], age: csv["Age"]));
}
}
return cows;
}
So now it does not matter which header comes first in the CSV being read.
The library allows for strongly typed parsing.
If Cow is defined with a default constructor and have the properties in the appropriate typed
public class Cow {
public int Age { get; set; }
public int Weight { get; set; }
}
ReadCowStream could be simplified to
private static IEnumerable<Cow> ReadCowStream(Stream source) {
using (var reader = new StreamReader(source)) {
var csv = new CsvReader(reader);
return csv.GetRecords<Cow>().ToList();
}
}
the CSV reader will parse the lines, create instances and assign the values by matching the headers to the property names.

You could store the header indices for example:
int weightIndex = Array.FindIndex(values, v => v == "Weight");
int ageIndex = Array.FindIndex(values, v => v == "Age");
Then access the values as follows:
cows.Add(new Cow(
weight: values[weightIndex],
age: values[ageIndex]));

With Cinchoo ETL - an open source library, you can do the csv parsing easily with few lines of code
public class Cow
{
public int Age { get; set; }
public int Weight { get; set; }
}
static void Main(string[] args)
{
string csv = #"Weight,Age
300,10
319,11
100,1
370,9";
foreach (Cow rec in ChoCSVReader<Cow>.LoadText(csv).WithFirstLineHeader())
{
Console.WriteLine($"Age: {rec.Age}, Weight: {rec.Weight}");
}
}

Reading multiple records kept in a text file

Basically i have the user open a text document that is formatted like this currently.
Burger.jpg,Double Down KFC,Food,30/06/95,This is a burger
it then splits the info into an array then into variables and then into text boxes.
obviously if i wanted multiple records i may have to format it differently, (thats what i need help with)
But if i had it like this what would be the most efficient way of taking these records from the text file and storing them separately so i can flick through them. For example with a combo box on my form. When the record is selected the form populates with that records data.
multiple records:
Burger.jpg,Double Down KFC,Food,30/06/95,This is a burger
Person.jpg,Smile,People,23/06/95,This is a Person
Here is my code currently for this part.
private void LoadFile()
{
StreamReader reader = new StreamReader(fileName);
content = reader.ReadLine();
doc = content.Split(',');
filename = Convert.ToString(doc[0]);
fileNameTextBox.Text = doc[0];
description = doc[1];
descriptionTextBox.Text = doc[1];
category = doc[2];
categoryComboBox.Text = doc[2];
//dateTaken = Convert.ToDouble(doc[3]);
dateTakenTextBox.Text = doc[3];
comments = doc[4];
commentsTextBox.Text = doc[4];
}
This code currently works but only for the first record as it is using one array, and i obviously will need multiple ways of storing the other lines.
I Think the best option if i was going to give it a guess would be to use a List of some sort with a Class that generates Records, but that is where i am stuck and need help.
(usually my questions on here get downvoted as i am not concise enough if that is the case comment and i will try to alter my question.
Thanks everyone.

I would create a class that holds the information of a record
public class ImageInfo
{
public string FileName { get; set; }
public string Description { get; set; }
public string Category { get; set; }
public DateTime Date { get; set; }
public string Comments { get; set; }
public override string ToString()
{
return FileName;
}
}
Now you can write a method that returns the image infos
public List<ImageInfo> ReadImageInfos(string fileName)
{
string[] records = File.ReadAllLines(fileName);
var images = new List<ImageInfo>(records.Length);
foreach (string record in records) {
string[] columns = record.Split(',');
if (columns.Length >= 5) {
var imageInfo = new ImageInfo();
imageInfo.FileName = columns[0];
imageInfo.Description = columns[1];
imageInfo.Category = columns[2];
DateTime d;
if (DateTime.TryParseExact(columns[3], "dd/MM/yy",
CultureInfo.InvariantCulture, DateTimeStyles.None, out d))
{
imageInfo.Date = d;
}
imageInfo.Comments = columns[4];
images.Add(imageInfo);
}
}
return images;
}
Now you can fill the textboxes with one of these records like this
List<ImageInfo> images = ReadImageInfos(fileName);
if (images.Count > 0) {
ImageInfo image = images[0];
fileNameTextBox.Text = image.FileName;
descriptionTextBox.Text = image.Description;
categoryComboBox.Text = image.Category;
dateTakenTextBox.Text = image.Date.ToShortDateString();
commentsTextBox.Text = image.Comments;
}
The advantage of this approach is that the two operations of reading and displaying the records are separate. This makes it easier to understand and modify the code.
You can add ImageInfo objects to a ComboBox or ListBox directly instead of adding file names if you override the ToString method in the ImageInfo class.
public override string ToString()
{
return FileName;
}
Add the items to a combo box like this:
myComboBox.Items.Add(image); // Where image is of type ImageInfo.
You can retrieve the currently selected item with:
ImageInfo image = (ImageInfo)myComboBox.SelectedItem;
Most likely you will be doing this in the SelectedIndexChanged event handler.
void myComboBox_SelectedIndexChanged(object sender, EventArgs e)
{
ImageInfo image = (ImageInfo)myComboBox.SelectedItem;
myTextBox.Text = image.FileName;
}

Create a class that resembles a row of your data, then iterate over the file, making your split and constructing a new class instance with your split data. Store this in a List<> (or some other appropriate structure) ensure you store it such that it can be referenced later. Don't change your UI as you are loading and parsing the file (as Mike has suggested), also as mike suggests you need to read until the EOF is reached (plenty of examples of this on the web) MSDN example.
Also, streamreader implements IDisposable, so you need to dispose of it, or wrap it in a using statement to clean up.
Example class, you could even pass the row in as a constructor argument:
public class LineItem
{
public string FileName { get; set; }
public string Description { get; set; }
public string Category { get; set; }
public DateTime DateTaken { get; set; }
public string Comments { get; set; }
public LineItem(string textRow)
{
if (!string.IsNullOrEmpty(textRow) && textRow.Contains(','))
{
string[] parts = textRow.Split(',');
if (parts.Length == 5)
{
// correct length
FileName = parts[0];
Description = parts[1];
Category = parts[2];
Comments = parts[4];
// this needs some work
DateTime dateTaken = new DateTime();
if (DateTime.TryParse(parts[3], out dateTaken))
{
DateTaken = dateTaken;
}
}
}
}
}

Your code is not iterating through the records within the file.
You want to continue reading until the end of the file.
while (content != eof)
{
// split content
// populate text boxes
}
But this will overwrite your text boxes with each pass of the loop.
Also, you want to separate your code - do not mix I/O process with code that updates the UI.
The name of the method implies you are loading a file, but the method is doing far more than that. I would suggest changing the method to read the file, split each record into a class object which then gets stored into an array - and return that array.
A separate method will take that array and populate your table or grid or whatever is in the UI. Ideally, you have the gridview bind to the array.

If you keep all your entries the same:
name,food,type,blah blah
name,food,type,blah blah
you can add another split into your code:
line = content.Split('\n');
foreach (line in filename)
{
doc = line.Split(',');
//do stuff...
As for the option for string multiple entries, a method I have used is implementing a list of Models:
class ModelName
{
string Name { get; set; }
string foodType { get; set; }
//etc...
public void ModelName()
{
Name = null;
foodType = null;
//etc...
}
}
List<Model> ModelList;
foreach (line in filename)
{
doc = line.Split(',');
Model.Name = doc[1];
//etc...
And have a different list, and a different Model for each type of entry (person or food)