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Why does my bubblesort code need - 2 after the structure.Length for it to work?

I am trying to understand why my productTable.Length has to be - 2 for my bubblesort code to work.
I created two int variables, Last_Position and i. I created one product variable called temp and one bool called swap which is set to false. I then set Last_Position to equal productTable.Length - 2.
This is where I fail to understand, from what I have read the .Length counts the amount of characters and returns the amount however since 1 counts as 0 in programming, you have to - 1 to have the cap be accurate (i.e 1000 = 999) which has remained true until this part.
For some reason - 1 will throw up an error when the program runs targeting this code: if (String.Compare(productTable[i].prodCode, productTable[i + 1].prodCode) > 0) and states "System.IndexOutOfRangeException: 'Index was outside the bounds of the array.'"
The code works when I set it to - 2 but I want to understand why that is.
struct product
{
public string prodCode;
public string description;
public double price;
public int quantity;
}
product[] productTable;
public void loadData()
{
string path = "C:\\Users\\5004303\\Documents\\productFile.csv";
int lineCount = File.ReadLines(path).Count();
productTable = new product[lineCount];
product currentProduct = new product();
try
{
StreamReader sr = new StreamReader(path);
string line;
int currentArrayLocation = 0;
while (!sr.EndOfStream)
{
line = sr.ReadLine();
string[] fields = line.Split(',');
currentProduct.prodCode = fields[0];
currentProduct.description = fields[1];
currentProduct.price = Convert.ToDouble(fields[2]);
currentProduct.quantity = Convert.ToInt32(fields[3]);
productTable[currentArrayLocation] = currentProduct;
currentArrayLocation++;
}
sr.Close();
}
catch (FileNotFoundException)
{
MessageBox.Show("An error occured. Could not find file 'productFile.csv'.");
}
}
public void listProducts()
{
int currentArrayLocation = 0;
for (currentArrayLocation = 0; currentArrayLocation < productTable.Length; currentArrayLocation++)
{
ListViewItem lvi = new ListViewItem();
lvi.Text = productTable[currentArrayLocation].prodCode;
lvi.SubItems.Add(Convert.ToString(productTable[currentArrayLocation].description));
lvi.SubItems.Add(Convert.ToString(productTable[currentArrayLocation].price));
lvi.SubItems.Add(Convert.ToString(productTable[currentArrayLocation].quantity));
lvProducts.Items.Add(lvi);
}
}
public void bubbleSort()
{
int last_Postion, i;
product temp;
last_Postion = productTable.Length - 2;
Boolean swap = false;
do
{
swap = false;
for (i = 0; i <= last_Postion; i++)
{
if (String.Compare(productTable[i].prodCode, productTable[i + 1].prodCode) > 0)
{
temp = productTable[i];
productTable[i] = productTable[i + 1];
productTable[i + 1] = temp;
swap = true;
}
}
}
while (swap == true);
}

Short answer:
Change
productTable.Lenght - 2 to productTable.Lenght - 1
and
for (i = 0; i <= last_Postion; i++) to for (i = 0; i < last_Postion; i++)
Explanation:
productTable.Lenght gives you the lenght of the list so productTable.Lenght - 1 is the last position in the list (0 to productTable.Lenght - 1).
In your "bubble" for loop inside the while you test against i+1 so i should only go up to the last_position - 1.
In your code when i == last_position then i + 1 is beyond the last position in the list.
Note: I did not check your code for validity, even if you make these changes, there may be other bugs.
Note on style, C# coding guidelines usually specify camel case for variable names, it is better to use lastPosition instead of last_Position. There are other styling "errors" in your code, such as declaring variables at the top of the function, using types instead of var. It may be some of this "errors" are course requirements, but a short read of any coding conventions document (e.g. https://learn.microsoft.com/en-us/dotnet/csharp/programming-guide/inside-a-program/coding-conventions) would be beneficial to you. Most work places have their own coding guidelines or adopt a public one, but on all of them are pretty similar.

c# how to store values from a file in an array [duplicate]

This question already has answers here:
C# parsing a text file and storing the values in an array
(3 answers)
Closed 5 years ago.
I am trying to store values in an array from reading from a file. I have the reading from a file part but I can't get it to store in an array because it gives me an error "Value cannot be null" because after the loop the value of my variable becomes null and the array cannot be null. Here's what I have. And I realize that the for loop probably isn't in the correct spot so any help with where to put it would be great.
Program p = new Program();
int MAX = 50;
int[] grades = new int[MAX];
string environment = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal) + "\\";
string path = environment + "grades.txt";
StreamReader myFile = new StreamReader(path);
string input;
int count = 0;
do
{
input = myFile.ReadLine();
if (input != null)
{
WriteLine(input);
count++;
}
} while (input != null);
for (int i = 0; i < count; i++)
{
grades[i] = int.Parse(input);
}

You start the for loop just after exiting from the while loop. And the condition to exit from the while loop is true when input is null. Of course this is not well accepted by Int.Parse.
Instead you can use a single loop, taking in consideration that you don't want to loop more than 50 times otherwise you exceed the array dimensions
int count = 0;
while((input = myFile.ReadLine()) != null && count < 50)
{
WriteLine(input);
grades[count] = int.Parse(input);
count++;
}
However you can have a more flexible way to handle your input if you use a List<int> instead of an array of integers. In this way you don't have to check for the number of lines present in your file
List<int> grades = new List<int>();
while((input = myFile.ReadLine()) != null)
grades.Add(int.Parse(input));

if we want to get really condensed
var grades = File.ReadAllLines(path).Select(l=>Int.Parse(l)).ToArray();

Utilize the Path.Combine() to help you in concatenating paths.
string environment = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal);
String fullPath = Path.Combine(environment, "grades.txt");
int[] grades = File.ReadAllLines(fullPath).Select(p => int.Parse(p)).ToArray<int>();
Console.WriteLine(grades);
Refer to https://www.dotnetperls.com/file-readalllines on how to use File.ReadAllLines() its very handy.
I'm using LINQ here, which sometimes simplifies things. Even though it looks a bit intimidating now. We read all lines, the result of that is then parsed by selecting each one and converting it to an integer then outputting an array of integers and saving that to grades.

Program p = new Program();
int MAX = 50;
int[] grades = new int[MAX];
string environment = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal) + "\\";
string path = environment + "grades.txt";
using (StreamReader myFile = new StreamReader(path))
{
string input;
int count = 0;
while((!myFile.EndOfStream) && (count < MAX))
{
input = myFile.ReadLine();
if (!String.IsNullOrWhiteSpace(input))
{
WriteLine(input);
grades[count] = int.Parse(input);
count++;
}
}
}
You should definitely use the "using" pattern around your stream object. Got rid of the for-loop for you while maintaining mostly your code and style. Your issue was that you weren't using the input value before moving on to the next line. You only ever had the last value in your original code.

Reading text file until a space and storing several values

I am creating an application to read and display Pokemon stats. Currently, I have 6 txt files, one for each stat. I have 6 arrays reading each txt file and displaying each stat in a label.
I want to condense this information into a single text file, splitting each stat by a " " to keep each Pokemon's data on a single line.
Current code if it helps explain the idea better:
using System;
using System.Windows.Forms;
using System.IO;
namespace Pokedex
{
public partial class Pokedex : Form
{
public Pokedex()
{
InitializeComponent();
}
//Read stat data from text files into string arrays
string[] HP = File.ReadAllLines("HP.txt");
string[] Atk = File.ReadAllLines("Atk.txt");
string[] Def = File.ReadAllLines("Def.txt");
string[] SpAtk = File.ReadAllLines("SpAtk.txt");
string[] SpDef = File.ReadAllLines("SpDef.txt");
string[] Spe = File.ReadAllLines("Spe.txt");
private void cbxPokemon_SelectedIndexChanged(object sender, EventArgs e)
{
//Get array index of currently selected Pokemon
int index = cbxPokemon.SelectedIndex;
//Get integer values out of the string arrays for appropriate use
int intHP = int.Parse(HP[index]);
int intAtk = int.Parse(Atk[index]);
int intDef = int.Parse(Def[index]);
int intSpAtk = int.Parse(SpAtk[index]);
int intSpDef = int.Parse(SpDef[index]);
int intSpe = int.Parse(Spe[index]);
//Update labels with stat values in string forme, could also assign intStat.ToString()
lblDexNum.Text = (index + 1).ToString("d3");
lblHP.Text = HP[index];
lblAtk.Text = Atk[index];
lblDef.Text = Def[index];
lblSpAtk.Text = SpAtk[index];
lblSpDef.Text = SpDef[index];
lblSpe.Text = Spe[index];
lblBST.Text = (intHP + intAtk + intDef + intSpAtk + intSpDef + intSpe).ToString();
//Update bar width based on stat value
barHP.Width = intHP;
barAtk.Width = intAtk;
barDef.Width = intDef;
barSpAtk.Width = intSpAtk;
barSpDef.Width = intSpDef;
barSpe.Width = intSpe;
//Disable Previous and Next buttons when they cannot be used
if (index == 0) { btnPrev.Enabled = false; }
else { btnPrev.Enabled = true; }
if (index == cbxPokemon.Items.Count - 1) { btnNext.Enabled = false; }
else { btnNext.Enabled = true; }
}
private void btnPrev_Click(object sender, EventArgs e)
{
cbxPokemon.SelectedIndex -= 1;
}
private void btnNext_Click(object sender, EventArgs e)
{
cbxPokemon.SelectedIndex += 1;
}
}
}
Ideally, the file would contain the 6 stats, for example "100 90 80 70 60 50" on each line, with each of those valued being stored.
Is there a simple way to read until a space, store that value, and keep doing that until the end of the line?

Yes, this is very simple to do. You can use the String.Split() method to break apart the lines into parsable pieces.
You can read the stats file in the same way you are now, except you would only need to read one file instead of six:
string[] lines = File.ReadAllLines("PokemonStats.txt");
Then, inside your cbxPokemon_SelectedIndexChanged method, you can retrieve the stats for a Pokemon like this:
//Get integer values out of the string for appropriate use
string line = lines[index];
string[] parts = line.Split(' ');
int intHP = int.Parse(parts[0]);
int intAtk = int.Parse(parts[1]);
int intDef = int.Parse(parts[2]);
int intSpAtk = int.Parse(parts[3]);
int intSpDef = int.Parse(parts[4]);
int intSpe = int.Parse(parts[5]);
Of course this assumes there will always be exactly 6 integer stats per line and they will all be in a specific order.

Try something like this:
static void Main(string[] args)
{
//list to store stats
List<string[]> pokemonStats = new List<string[]>();
//get a reader on the file
using (StreamReader reader = new StreamReader("TextFile1.txt"))
{
//while we still have lines to read
while (!reader.EndOfStream)
{
//get the line of stats
string line = reader.ReadLine();
//split it on the ' ' character and store it in our list of pokemon stats
pokemonStats.Add(line.Split(' '));
}
}
//we have them all so do something, like print to screen
foreach (string[] pokemon in pokemonStats)
{
foreach (string stat in pokemon)
Console.Write(stat + " ");
Console.WriteLine();
}
Console.ReadLine();
}
Where TextFile1.txt contains; which also happens to be the output...
1 1 1 1 1 1
2 2 2 2 2 2
3 3 3 3 3 3

Ideally, the file would contain the 6 stats, for example "100 90 80 70 60 50" on each line, with each of those valued being stored.
So this solution is actually very simple, assuming you have a file that looks like this:
100
90
80
70
60
50
You could write code that looks like this:
public string[] ReadStats(string fileName)
{
return File.ReadAllLines(fileName);
}
This would return:
[ "100", "90", "80", "70", "60", "50" ]
This is obviously an over-simplified version that does not checking on whether the file exists, whether there are more than 6 lines, etc. But it gets the idea across, and you could enhance it to suit your needs.
The answer to your main question:
Is there a simple way to read until a space, store that value, and keep doing that until the end of the line?
This is a bit more complicated, but this should work:
public IEnumerable<string[]> ReadAllPokemonStats(string fileName)
{
List<string[]> allPokemon = new List<string[]>();
string[] allStats = new string[6];
var allText = File.ReadAllText(fileName);
int nextStatIndex = 0;
string thisStat;
for(int i=0; i < allText.Length; i++)
{
var nextChar = allText[i];
if(nextChar == ' ')
{
allStats[nextStatIndex] = thisStat;
nextStatIndex++;
continue;
}
if(nextChar == '\r')
{
allPokemon.Add(allStats);
nextStatIndex = 0;
allStats = new string[6];
continue;
}
thisStat += nextChar.ToString();
}
return allPokemon;
}
Again, the above code is not perfect, for example it reads the entire file into memory so there's a potential attack vector there. It also does not ensure that the stats are actually numeric, but neither did your code (it would just blow up on the int.Parse()). But again, it gives you the general idea. You can see this approach is actually a lot more complex that reading each stat line by line.

I am thinking that each file is a one column file that represents one type of stat. If this is correct, you can try this:
Perhaps creating a class the represents all the stats that you are loading and then treat that as an array or a dictionary to fetch the proper stat or to create a single stat file.
public class PokemonStat
{
public int Hp { get; set; }
public int Atk { get; set; }
public int Def { get; set; }
public int SpAtk { get; set; }
public int SpDef { get; set; }
public int Spe { get; set; }
}
Then in your executing file:
var newPokemanData = new Dictionary<int, PokemonStat>();
var fileNames = new string[] { "Hp.txt", "Atk.txt", "Def.txt", "SpAtk.txt", "SpDef.txt", "Spe.txt" }
foreach (var fileName in fileNames)
{
var lineNumber = 0;
using (var stream = new StreamReader(fileName))
{
while (!stream.EndOfStream)
{
var singleStat = stream.ReadLine();
if (!newPokemanData.Keys.Contains(lineNumber))
{
newPokemanData.Add(lineNumber, new PokemonStat());
}
switch(fileName)
{
case "Hp.txt":
newPokemanData[lineNumber].Hp = int.Parse(singleStat);
break;
case "Atk.txt":
newPokemanData[lineNumber].Atk = int.Parse(singleStat);
break;
case "Def.txt":
newPokemanData[lineNumber].Def = int.Parse(singleStat);
break;
case "SpAtk.txt":
newPokemanData[lineNumber].SpAtk = int.Parse(singleStat);
break;
case "SpDef.txt":
newPokemanData[lineNumber].SpDef = int.Parse(singleStat);
break;
case "Spe.txt":
newPokemanData[lineNumber].Spe = int.Parse(singleStat);
break;
default:
Console.WriteLine("Error");
break;
}
lineNumber++;
}
}
}
using (var unifiedStats = new StreamWriter("unifieldFile.txt"))
{
foreach (var line in newPokemanData.Keys)
{
//write to a file
unifiedStats.WriteLine(newPokemanData[line].Hp.ToString() + " " +
newPokemanData[line].Atk.ToString() + " " +
newPokemanData[line].Def.ToString() + " " +
newPokemanData[line].SpAtk.ToString() + " " +
newPokemanData[line].SpDef.ToString() + " " +
newPokemanData[line].Spe.ToString() + " "
);
}
}
//

Auto Incrementing file names?

I have a list of files like so
abc.txt
pas.txt
tempr.txt
What I would like to do is to append english alphabets to theese file names ..
the result should look like this
abc_a.txt
pas_b.txt
tempr_c.txt
This process should continue till the last character (i.e 'z'). if there are more files then the file names would become
abc_a.txt
pas_b.txt
tempr_c.txt
.................
filename_z.txt
anotherfilename_a001.txt
Notice that the counter was again reset to the first character except an integer was attached to it.
This is the code that i have right now. Please note that it is NOT working ..
string alphabets= "abcdefghijklmnopqrstuvwxyz";
List<string> filenames = new List<string>();
filenames.Add("test1.txt");
filenames.Add("newfile.cs");
filenames.Add("test2.txt");
filenames.Add("newfile2.cs");
string currentFileNmae = string.Empty;
foreach(string s in filenames) {
char usedAlphabet = new char();
for(int i = 0;i<=alphabets.Length-1;i+=11) {
usedAlphabet.Dump();
alphabets[i].Dump();
if(usedAlphabet != alphabets[i] )
{
if(currentFileNmae!= s)
{
string.Format("{0}--{1}",s,alphabets[i]).Dump();
usedAlphabet = alphabets[i];
currentFileNmae = s;
}
}
break;
}
}
I am part of a team that's building a file renamer tool for our internal purposes and hence i need this code. This is part of the our enumertation functionality that we have planned.
Please suggest.
thanks

Try starting here:
using System.Diagnostics;
using System.IO;
string filename = #"C:\Foo\Bar.txt";
for (int count = 0; count < 100; count++)
{
char letter = (char)((int)'a' + count % 26);
string numeric = (count / 26) == 0 ? "" : (count / 26).ToString("000");
Debug.Print(Path.GetFileNameWithoutExtension(filename) + "_" + letter + numeric + Path.GetExtension(filename));
}
Substitute your own loop to go through the filenames and use Path to manipulate the pieces/parts of the names.
The renaming, IIRC, can be handled by File.Move. Surround it with a try/catch to implement the name collision logic.

Had no coffee yet, but this should do.
List<string> files = new List<string>();
int charIndex = 0;
int numericIndex = -1;
foreach (var file in files.Select(path => new FileInfo(path)))
{
// Create new Filename - This may needs some tuning
// to really remove only the extension ad the end
// It doesnt take care of things like
// file.bmp.bmp.bmp ...
string newFileName = String.Format("{0}_{1}{2}.{3}",
file.FullName.Replace(file.Extension,String.Empty),
(char)(charIndex++ + 97),
(numericIndex > -1 ? String.Format("{0:D4}", numericIndex) : String.Empty),
file.Extension);
// Rename the File
file.MoveTo(newFileName);
// Increment Counters.
if (charIndex > 25)
{
charIndex = 0;
numericIndex++;
}
}

You can try something like this
const string directory = #"C:\\wherever";
string[] fiNames = new string[]{ "abc", "pas", "etc",};
char[] alphabet = "abcdefghijklmnopqrstuvwxyz".ToCharArray();
int x = 0;
string ending = "";
for(int i = fiNames.Count()-1; i>=0; i--)
{
if(x%26==0)
{
x=0
if( ending=="")
ending="1";
else
ending=(System.Convert.ToInt32(ending)+1).ToString();
}
System.IO.File.Move(directory+fiNames[i], fiNames[i]+alphabet[x].ToString()+ending);
x++;
}

Checking a TXT Doc against anther TXT Doc

I will do what I can to get a snipit of the txt files on here for you to look at. most of them are class and it will take a bit of work for me to do that. The idea is to take a txt file with say a list of over 500 places run them against a list of 50 places and pull out the ones that match. As I said I have tried many diffrent ways, well all the ones I know, and I can not seem to get it to work right. I am trying to take the following code and have it do the above action. Does that help.
InPutBox = Input.Text;
int x = 1;
var lines = Input.Text.Split(new string[] { Environment.NewLine },StringSplitOptions.None);
for (var index = 0; index < lines.Length; index++)
{
var line = lines[index];
do
{
x++;
System.Console.WriteLine("'{0}'", InPutBox);
bool test1 = InPutBox.StartsWith("TAG");
bool test2 = InPutBox.EndsWith("TAG");
if (test1 && test2)
{
int first = InPutBox.IndexOf("TAG");
int last = InPutBox.LastIndexOf("TAG");
InPutBox = InPutBox.Substring(first, last - first);
}
}
while (x < 50);
System.Console.WriteLine("'{0}'", line);
if ((line.StartsWith("TAG") && line.EndsWith("TAG")))
{
MessageBox.Show("These are errors in line" + index + ": " + line);
break;
}
}