How do I convert string[] to int[]?

Question

How exactly do I convert an array of strings to an array of integers? I won't let me run the program because of this minor problem. Any ideas how to do so? I have to pull a list of numbers from a file, read them to the console, then get the average number and display it to the user.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;

namespace lab25LEA
{
    class Program
    {
        const int MAX = 50; 

        static void Main(string[] args)
        {
            // In your program create an array of 50 integers
            // to hold the data that comes from the file.
            int[] numbers = new int[MAX];

            // Your program must get the path to the user's Documents folder as described in the reading material on File Paths.
            // The name of the file will be "grades.txt". Code this file name right in your program. 
            // No user input is required to get the file name.

            // Create a StreamReader object, 
            // using this path. This will open the file.
            StreamReader data = new StreamReader("grades.txt");
            string fromFile;
            int count = 0;

            // Write a loop that reads data from the file, 
            // until it discovers the end of the file.
            do
            {
                fromFile = data.ReadLine();
                // As each integer value is read in, display it, and store it in the array.
                if (fromFile != null)
                {
                    // Using the concepts taught earlier about partially filled arrays, 
                    // write a method that takes the array as a parameter and calculates and returns the average 
                    // value of the integers stored in the array
                    int[] dataArray = fromFile.Split();

                    numbers[count] = dataArray[1];
                    count++;
                }
            } while (fromFile != null);

            // Output the average.
            AverageScore(numbers);

            Console.ReadLine();
        }

        static void AverageScore(int[] numbers)
        {
            int sum = numbers.Sum();
            int average = sum / numbers.Length;
        }
    }
}

Kevin Ji · Answer 1 · 2014-12-12T04:32:27.317

1

Just use a Select to convert each element into the integer equivalent:

string[] strArray = fromFile.Split();
int[] dataArray = strArray.Select(int.Parse).ToArray();

edited Dec 12 '14 at 04:32

answered Dec 12 '14 at 04:13

Kevin Ji

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Kavindu Dodanduwa · Answer 2 · 2014-12-12T04:17:45.623

Try this

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;

namespace lab25LEA
{
    class Program
    {
        const int MAX = 50; 

        static void Main(string[] args)
        {
            // In your program create an array of 50 integers
            // to hold the data that comes from the file.
            int[] numbers = new int[MAX];

            // Your program must get the path to the user's Documents folder as described in the reading material on File Paths.
            // The name of the file will be "grades.txt". Code this file name right in your program. 
            // No user input is required to get the file name.

            // Create a StreamReader object, 
            // using this path. This will open the file.
            StreamReader data = new StreamReader("grades.txt");
            string fromFile;
            int count = 0;

            // Write a loop that reads data from the file, 
            // until it discovers the end of the file.
            fromFile = data.ReadLine();

            while (fromFile != null){

                // As each integer value is read in, display it, and store it in the array.
                if (fromFile != null)
                {
                    // Using the concepts taught earlier about partially filled arrays, 
                    // write a method that takes the array as a parameter and calculates and returns the average 
                    // value of the integers stored in the array
                    int[] dataArray = fromFile.Split(" ");

                    numbers[count] = Convert.ToInt32(dataArray[1]);
                    count++;

                    fromFile = data.ReadLine();
                }
            }

            // Output the average.
            AverageScore(numbers);

            Console.ReadLine();
        }

        static void AverageScore(int[] numbers)
        {
            int sum=0;
            int average=0;
            if(numbers.length > 0){
                 sum = numbers.Sum();
                 average = sum / numbers.Length;
            }

            Console.WriteLine("Average is :{0}",average);
        }
    }
}

How do I convert string[] to int[]?

2 Answers2