Develop Reference

How can I store a variable in an array

I am trying to connect a "serial-code" or whatever to variable to be printed as a string. The code will be generated from 5 sensors and will give me a 5 digit number (sensorValue)(this calculation is not included in the example and I have simplified it to 3 digits). I add an "s" before the code so that I can make a variable with the same name. However I cannot seem to store a variable in the array as I get the message that the variables are assigned but is never used. It clearly cannot be attached the way i'm doing it at least. But I hope that I illustrates what I intend to do.
So I get the "serial-code" s123 but I need to convert it to another string. There will be approximately 3000 different "serial-codes" with a string attached to each one of them. I'm sure I can make 3000 "if" statements but I am afraid that would be very slow.
Any ideas how I can overcome this issue of mine?
Thanks in advance!
using System;
using System.Linq;
namespace TestingArray
{
static void Main(string[] args)
{
// Trying to assign a value to the string that is used in the array
var s123 = "Hello";
var s321 = "Bye";
var s111 = "Thanks";
// Creating the array to be used
object [] arr = { "s123", "s321", "s111" };
// A simulation of what the future sensor would read
int sensorValue;
sensorValue = 123;
// Creating a "code" with the sensorValue to find it in the array.
string doThis = "s" + sensorValue
;
// I want to display the string which corresponds to this "serial-code" string.
Console.Write(arr.Contains(doThis));
}
}

Sounds like you want a dictionary. The key is the name and the value is the sensor data.
static void Main(string[] args)
{
Dictionary<string, string> sensors = new Dictionary<string, string> {
{"s123", "Hello"},
{"s321", "Bye"},
{"s111", "Thanks"}
};
// A simulation of what the future sensor would read
int sensorValue;
sensorValue = 123;
// Creating a "code" with the sensorValue to find it in the array.
string doThis = "s" + sensorValue;
if (sensors.ContainsKey(doThis)) {
Console.WriteLine(sensors[doThis]);
}
}

C# Converting an array to a list

I am working on an assignment that deals with file input and output. The instructions are as follows:
Write a program to update an inventory file. Each line of the inventory file will have a product number, a product name and a quantity separated by vertical bars. The transaction file will contain a product number and a change amount, which may be positive for an increase or negative for a decrease. Use the transaction file to update the inventory file, writing a new inventory file with the update quantities. I have provided 2 Input files to test your program with as well as a sample output file so you see what it should look like when you are done.
Hints:
This program requires 3 files
Initial Inventory File
File showing updates to be made
New Inventory File with changes completed
Use Lists to capture the data so you don’t have to worry about the number of items in the files
Each line of the Inventory file looks something like this:
123 | television | 17
I have also been given the basic structure and outline of the program:
class Program
{
public class InventoryNode
{
// Create variables to hold the 3 elements of each item that you will read from the file
// Make them all public
public InventoryNode()
{
// Create a constructor that sets all 3 of the items to default values
}
public InventoryNode(int ID, string InvName, int Number)
{
// Create a constructor that sets all 3 of the items to values that are passed in
}
public override string ToString() // This one is a freebie
{
return IDNumber + " | " + Name + " | " + Quantity;
}
}
static void Main(String[] args)
{
// Create variables to hold the 3 elements of each item that you will read from the file
// Create variables for all 3 files (2 for READ, 1 for WRITE)
List<InventoryNode> Inventory = new List<InventoryNode>();
InventoryNode Item = null;
// Create any other variables that you need to complete the work
// Check for proper number of arguments
// If there are not enough arguments, give an error message and return from the program
// Otherwise
// Open Output File
// Open Inventory File (monitor for exceptions)
// Open Update File (monitor for exceptions)
// Read contents of Inventory into the Inventory List
// Read each item from the Update File and process the data
// Write output file
//Close all files
return;
}
}
There is a lot of steps to this problem but right now I am only really concerned with how to read the inventory file into a list. I have read files into arrays before, so I thought I could do that and then convert the array to a list. But I am not entirely sure how to do that. Below is what I have created to add to the main method of the structure above.
int ID;
string InvName;
int Number;
string line;
List<InventoryNode> Inventory = new List<InventoryNode>();
InventoryNode Item = null;
StreamReader f1 = new StreamReader(args[0]);
StreamReader f2 = new StreamReader(args[1]);
StreamWriter p = new StreamWriter(args[2]);
// Read each item from the Update File and process the data
while ((line = f1.ReadLine()) != null)
{
string[] currentLine = line.Split('|');
{
ID = Convert.ToInt16(currentLine[0]);
InvName = currentLine[1];
Number = Convert.ToInt16(currentLine[2]);
}
}
I am a bit hung up on the Inventory Node Item = null; line. I am not really sure what this is supposed to be doing. I really just want to read the file to an array so I can parse it and then pass that data to a list. Is there a way to do that that is something similar to the block I have written? Maybe there is a simpler way. I am open to that, but I figured I'd show my train of thought.

There is not need to add everything to an array and then convert it to the list. InventoryNode Item = null is there to represent a line from the file.
You're pretty close. You just need to instantiate the InventoryNode and feed it the results of the split() method.

You're almost there. You already have fetched ID, InvName and Number, so you just have to instantiate the InventoryNode:
Item = new InventoryNode(...);
And then add Item to your list.
Note that Inventory Node Item = null; is not doing much; it just declares a variable that you can use later. This wasn't strictly necessary as the variable could have been declared inside the loop instead.

Read CSV file to multiple integers

It has been a few years since i have messed with C# or programming for that matter. I am attempting to read a CSV file to multiple integers. The CSV file is formatted as follows
box1,3
box2,6
box3,10
...
box160,1
So far for my code i have the below. The TextFieldParser i got off of another question. I am not sure if that is even what i need. I do not need to keep the information before the "," on the CSV file i just need the information after the "," to correspond with the correct int in my code. Any help or pointers would be much appreciated.
int box1;
int box2;
int box3;
...
int box160;
using (TextFieldParser parser = new TextFieldParser(#"C:\SprinklerTimer\DailySprinklerTimer.csv"))
{
parser.TextFieldType = FieldType.Delimited;
parser.SetDelimiters(",");
while (!parser.EndOfData)
{
//Processing row
string[] fields = parser.ReadFields();
foreach (string field in fields)
{
//TODO: Process field
}
}
}

For starters manually making 160 box integers is very inefficient. Try using an array.
int[] box; // declare numbers as an int array of any size
box = new int[160]; //New box array for 0-159
and you can either do the same for the value, I.e. a value[] array or what I would is make box a struct instead of int, where the struct has two integers.
struct SimpleStruct
{
int name, value;
}
SimpleStruct[] box; // declare numbers as an int array of any size
box = new SimpleStruct[160]; //New box array for 0-159
And to go on to your actual question, I would recommend this question which will help if you implement my above changes.
Read CSV files to two arrays c#

Manipulating Values in Dictionary

So I have a dictionary whose index is an int, and whose value is a class that contains a list of doubles, the class is built like this:
public class MyClass
{
public List<double> MyList = new List<double>();
}
and the dictionary is built like this:
public static Dictionary<int, MyClass> MyDictionary = new Dictionary<int, MyClass>();
I populate the dictionary by reading a file in line by line, and adding the pieces of the file into a splitstring, of which there is a known number of parts (100), then adding the pieces of the string into the list, and finally into the dictionary. Here's what that looks like:
public void DictionaryFiller()
{
string LineFromFile;
string[] splitstring;
int LineNumber = 0;
StreamReader sr = sr.ReadLine();
while (!sr.EndOfStream)
{
LineFromFile = sr.ReadLine();
splitstring = LineFromFile.Split(',');
MyClass newClass = new MyClass();
for (int i = 1; i < 100; i++)
{
newClass.MyList.Add(Convert.ToDouble(splitstring[i]));
}
MyDictionary.Add(LineNumber, MyClass);
LineNumber++;
}
}
My question is this: is I were to then read another file and begin the DictionaryFiller method again, could I add terms to each item in the list for each value in the dictionary. What I mean by that is, say the file's 1st line started with 10,23,15,... Now, when I read in a second file, lets say its first line begins with 10,13,18,... what I'm looking to have happen is for the dictionary to have the first 3 doubles in its value-list (indexed at 0) to then become 20,36,33,...
Id like to be able to add terms for any number of files read in, and ultimately then take their average by going through the dictionary again (in a separate method) and dividing each term in the value-list by the number of files read in. Is this possible to do? Thanks for any advice you have, I'm a novice programmer and any help you have is appreciated.

Just Replace
newClass.MyList.Add(Convert.ToDouble(splitstring[i]))
with
newClass.MyList.Add(Convert.ToDouble(splitstring[i]) + MyDictionary[LineNumber].GetListOfDouble()[i])
and then replace
MyDictionary.add(Linenumber, Myclass)
with
MyDictionary[linenumber] = MyClass
Just makes sure that the MyDictionary[LineNumber] is not null before adding it :)
Something like this would work
If(MyDictionary[LineNumber] == null)
{
MyDictionnary.add(LIneNUmber, new List<double>());
}
If(MyDictionary[LineNUmber][i] == null)
{
return 0;
}
My solution does not care about list size and it done at reading time not afterward, which should be more efficient than traversing your Dictionary twice.

var current = MyDictionary[key];
for(int i = 0; i < current.MyList.Length; i++)
{
current.MyList[i] = current.MyList[i] + newData[i];
}
Given both lists have same length and type of data.
You can get the custom object by key of the dictionary and then use its list to do any operation. You need to keep track of how many files are read separately.

Naming a variable from a text file

I'm making a program in C# that uses mathematical sets of numbers. I've defined the class Conjunto (which means "set" in spanish). Conjunto has an ArrayList that contains all the numbers of the set. It also has a string called "ID" which is pretty much what it sounds; the name of an instance of Conjunto.
The program have methods that applies the operations of union, intersection, etc, between the sets.
Everything was fine, but now i've a text file with sentences like:
A={1,2,3}
B={2,4,5}
A intersection B
B union A
And so on. The thing is, i don't know how many sets the text file contains, and i don't know how to name the variables after those sentences. For example, name an instance of Conjunto A, and name another instance B.
Sorry for the grammar, english is not my native language.
Thanks!

It's pretty complicated to create varaibles dynamically, and pretty useless unless you have some already existing code that expects certain variables.
Use a Dictionary<string, Conjunto> to hold your instances of the class. That way you can access them by name.

First off, If you don't target lower version than .Net 2.0 use List instead of ArrayList. If I were you I wouldn't reinvent the wheel. Use HashSet or SortedSet to store the numbers and then you can use defined union and intersection.
Secondly, what is your goal? Do want to have just the output set after all operations? Do you want to read and store all actions and them process it on some event?

First of all, your program is taken from bad side. I would advice to start making new one. One of ways to name "variables" dynamicaly is by making class objects and editing their properties.
This is what I made as a starting platform:
First af all I have crated a class called set
class set
{
public string ID { get; set; }
public List<int> numbers { get; set; }
}
Then I have made the code to sort whole textfile into list of those classes:
List<set> Sets = new List<set>();
string textfile = "your text file";
char[] spliter = new char[] { ',' }; //switch that , to whatever you want but this will split whole textfile into fragments of sets
List<string> files = textfile.Split(spliter).ToList<string>();
int i = 1;
foreach (string file in files)
{
set set = new set();
set.ID = i.ToString();
char[] secondspliter = new char[] { ',' }; //switch that , to whatever you want but this will split one set into lone numbers
List<string> data = textfile.Split(secondspliter).ToList<string>();
foreach (string number in data)
{
bool success = Int32.TryParse(number, out int outcome);
if (success)
{
set.numbers.Add(outcome);
}
}
i++;
Sets.Add(set);
}
Hope it helps someone.