I'm looking for a way to pass information from a text file into a constructor so that I can create an array of that constructor object with each object in the array holding information from the rows of the text file.

The constructor is formatted as follows:

public Member(string name, int number, decimal rate, double hours)

While the text file is formatted as such:

Eric Wallace,    352456, 15.88, 32.20
Clara Kell,     233424, 35.88, 18.76
Darren Price,   656795, 27.82, 20.25
etc...

and each Member will go into an array.

In the end, what I need is for each row to be split up and passed to the constructor in a way where each row becomes its own member in an array so that they can be output one after another in a loop or called individually as rows.

CodePudding user response：

My approach would begin with making an interface that all my "buildable" data types will implement. I want my data models deciding how they are built from a string:

    public interface IBuildableFromString
    {
        public IBuildableFromString Build(string str, string seperator = ",");
    }

Then make Member implement it like so:

    public class Member : IBuildableFromString
    {
        public string Name { get; set; }
        public int Number { get; set; }
        public decimal Rate { get; set; }
        public double Hours { get; set; }

        public Member() { }
        public Member(string name, int number, decimal rate, double hours)
        {
            Name = name;
            Number = number;
            Rate = rate;
            Hours = hours;
        }

        public IBuildableFromString Build(string str, string seperator = ",")
        {
            try
            {
                string[] parts = str.Split(seperator);
                return new Member(parts[0], int.Parse(parts[1]), 
                    decimal.Parse(parts[2]), double.Parse(parts[3]));
            }
            catch
            {
                return null;
            }
        }
    }

Then the method to read the file and build the object data:

        public static T[] BuildData<T>(string filePath) where T : 
                                                        IBuildableFromString, new()
        {
            List<T> dataObjects = new List<T>();
            string[] lines = File.ReadAllLines(filePath);

            foreach (string line in lines)
            {
                if (!String.IsNullOrEmpty(line))
                {
                    var newMember = new T().Build(line);
                    if (newMember != null)
                        dataObjects.Add((T)newMember);
                }
            }

            return dataObjects.ToArray();
        }

Lastly, call the function above like so:

        static void Main(string[] args)
        {
            var data = BuildData<Member>(@"path_to_your_file.txt");
        }

It probably needs more error checking, but this was the most extensible way I could think of doing it. Cheers!

CodePudding user response：

As long as your file is well-formed, then this would work:

Member[] members =
    File
        .ReadLines(@"mytextfile.txt")
        .Select(x => x.Split(',').Select(y => y.Trim()).ToArray())
        .Select(x => new Member(x[0], int.Parse(x[1]), decimal.Parse(x[2]), double.Parse(x[3])))
        .ToArray();

CodePudding user response：

I will use StreamReader to read the txt file, then use replace to eliminate spaces, and then use split to split the data.

Make Member implement it like so:

public class Member {
            public string Name { get; set; }
            public int Number { get; set; }
            public decimal Rate { get; set; }
            public double Hours { get; set; }
            public Member(string name, int number, decimal rate, double hours) {
                Name = name;
                Number = number;
                Rate = rate;
                Hours = hours;
            }
        }

Call the data like this:

foreach (var item in members) {
                Console.WriteLine($"{ item.Name}  { item.Number}  { item.Rate}   { item.Hours}");
            }

Total code:

using System;
using System.Collections.Generic;
using System.IO;

namespace ConsoleApp2 {
    class Program {
        static void Main(string[] args) {
            List<Member> members = new List<Member>();  
            try {
                // Create an instance of StreamReader to read from a file.
                // The using statement also closes the StreamReader.
                using (StreamReader sr = new StreamReader(@"C:\demo\de.txt")) {
                    string line;
                    // Read and display lines from the file until the end of
                    // the file is reached.
                    while ((line = sr.ReadLine()) != null) {
                        line = line.Replace(" ", "");
                        string[] tmp = line.Split(',');
                        string name = tmp[0];
                        int number = Convert.ToInt32(tmp[1]);
                        decimal rate = Convert.ToDecimal(tmp[2]);
                        double hours = Convert.ToDouble(tmp[3]);
                        members.Add(new Member(name, number, rate, hours));                    
                    }
                }
            } catch (Exception e) {
                // Let the user know what went wrong.
                Console.WriteLine("The file could not be read:");
                Console.WriteLine(e.Message);
            }
            foreach (var item in members) {
                Console.WriteLine($"{ item.Name}  { item.Number}  { item.Rate}   { item.Hours}");
            }

            Console.ReadLine();
        }

        public class Member {
            public string Name { get; set; }
            public int Number { get; set; }
            public decimal Rate { get; set; }
            public double Hours { get; set; }
            public Member(string name, int number, decimal rate, double hours) {
                Name = name;
                Number = number;
                Rate = rate;
                Hours = hours;
            }
        }
    }
}

If you have questions, please add a comment.