Receive data in a matrix c#

Question

Hello,

I was testing code to learn how to mess with the matrix, but I’m not able to store broken numbers in the variable.

he of the error of System.IndexOutOfRangeException and I can’t solve.

Someone could give me a light.

    {
        Boolean stop = true;
            int x = 0;
            double[] dados = new double[x];
        do
        {

            Console.WriteLine("Digite um numero");
            dados[x] = double.Parse(Console.ReadLine());
            x += 1;
            if (Console.ReadKey().Key != ConsoleKey.Y)
            {
                stop = false;
            }
        } while (stop);

        Console.WriteLine("Dados recebidos");
        for(int i = 0; i < dados.Length; i++)
        {
            Console.WriteLine(dados[i]);
        }
        Console.ReadKey();

    }

Answer 1

I believe you’re using Array for some kind of academic work, hence the use of List should be out of the question. Resizing a Array, something that is quite simple and direct using the Array.Resize (Array.Resize(T[], Int32) Method).

Using its base code, it would look that way:

int x = 0;
double[] dados = new double[1];

do
{
    Console.WriteLine("Digite um numero");
    dados[x] = double.Parse(Console.ReadLine());
    x++;

    if (Console.ReadKey().Key == ConsoleKey.Y)
        break;

    Array.Resize(ref dados, x + 1);
} while (true);

Console.WriteLine("Dados recebidos");

for (int i = 0; i < dados.Length; i++)
{
    Console.WriteLine(dados[i]);
}

Console.ReadKey();

Answer 2

Gustavo,

In your code, you create an array with the size of x, which in the case is zero:

int x = 0;
double[] dados = new double[x];

With this, you have an array of size zero, so when trying to access the index of the same:

dados[x] = double.Parse(Console.ReadLine());

You have the mistake that System.Indexoutofrangeexception

---

You can change the code to have a fixed size array by assigning a size to the array:

double[] dados = new double[10]; //Agora o array tem o tamanho de dez

And in the while condition, have a new check, to avoid typing more than the array supports, an example would be like this:

if (x < dados.Length)
{
    Console.WriteLine("Digite Y para continuar digitando valores:");

    if (Console.ReadKey().Key != ConsoleKey.Y || x >= dados.Length)
    {
        stop = false;
    }
}
else
{
    stop = false;
}

In the end, your code would look something like this:

using System;

class ArrayTeste {
  static void Main()
  {
    Boolean stop = true;
    int x = 0;
    double[] dados = new double[3];

    do
    {
        Console.WriteLine("\nDigite um numero:");
        dados[x] = double.Parse(Console.ReadLine());

        x += 1;

        if (x < dados.Length)
        {
            Console.WriteLine("Digite Y para continuar digitando valores:");

            if (Console.ReadKey().Key != ConsoleKey.Y)
            {
                stop = false;
            }
        }
        else
        {
            stop = false;
        }
    } while (stop);

    Console.WriteLine("\nDados recebidos");

    for(int i = 0; i < dados.Length; i++)
    {
        Console.WriteLine(dados[i]);
    }

    Console.ReadKey();
  }
}

Note: The do/while would be easily exchanged for a FOR, since you knows the size of the array.

---

Maybe, you are interested in lists, see your code using list, it is much simpler... And with foreach:

using System;
using System.Collections.Generic;

class ListTeste {
  static void Main()
  {
    Boolean stop = true;
    List<double> dados = new List<double>();

    do
    {
        Console.WriteLine("\nDigite um numero:");
        dados.Add(double.Parse(Console.ReadLine()));

        Console.WriteLine("Digite Y para continuar digitando valores:");

        if (Console.ReadKey().Key != ConsoleKey.Y)
        {
            stop = false;
        }
    } while (stop);

    Console.WriteLine("\nDados recebidos");

    foreach(double valor in dados)
    {
        Console.WriteLine(valor);
    }

    Console.ReadKey();
  }
}

The list does not have a predefined size, so I can keep the while while you have the patience to type numbers.

---

Finally, you can create the matrix based on an informed number:

int tamanho = int.Parse(Console.ReadLine());
double[] dados = new double[tamanho];
Console.WriteLine(dados.Length);