Override .ToString method c#

Question

Okay, so I wrote this program out of the exercise of a C# programming book (I'm trying to learn here) and it asks for " Override the ToString() method to return all data members ".

Have I done this correctly? Or have I just successfully wrote code that compiles but does nothing. What is the purpose of ToString ?

I have spent about 30 minutes looking at other posts on this and havn't figured it out, So I decided to make this.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication297
{
class Program
{
    static void Main(string[] args)
    {
        String name = "Stormtrooper";
        Employee s = new Employee(name);
        Console.WriteLine("The type of hire is a {0}", s.Name);
        Console.WriteLine("The identification number is {0}", s.Number);
        Console.WriteLine("The date of hire is {0} ABY", s.Date);
        Console.WriteLine("The standard galactic salary is...{0:C}", s.Salary);

    }

    class Employee
    {
        private string _name;
        private string _number;
        private int _date;
        private int _salary;
        public string Name
        {
            get
            {
                return _name;
            }
        }

        public string Number
        {
            get
            {
                return _number;
            }
        }

        public int Date
        {
            get
            {
                return _date;
            }
        }
        public int Salary
        {
            get
            {
                return _salary;
            }
        }
        public Employee(string n)
        {
            _name = n;
            _number = "AA23TK421";
            _date = 4;
            _salary = 800;
        }
    }

    public override string ToString()

    {
        return "_name + _number + _date + _salary".ToString();
    }
}
}

Answer 1

You are returning a string that just says the phrase _name + _number + _date + _salary .

What you likely wanted to do is build a string using those fields. If you wanted them all mushed together Concat would work, but it would be highly un-readable

public override string ToString()
{
    return String.Concat(_name, _number, _date, _salary);
}

However what would be better is to use Format and include labels with the values

public override string ToString()
{
    return String.Format("Name:{0}, Number:{1}, Date:{2}, Salary:{3}",_name, _number, _date, _salary);
}

---

If you are using C# 6 or newer you can use the following cleaner format

public override string ToString()
{
    return $"Name:{_name}, Number:{_number}, Date:{_date}, Salary:{_salary}";
}

Which is the exact same logic as the previous String.Format version.

Answer 2

The reason people override the ToString() method is to have a default string representation of your object, usually for display to the user or in a log or console, like this:

Console.WriteLine(yourClassObject);

If you do not override the ToString() , then its default implementation is to return the fully qualified name of your object, like this:

YourNamespace.YourClassName

By changing the inherited implementation (from System.Object ), then you can make a nicer (read: prettier) representation, like this:

public override string ToString()
{
    return String.Format("This instance of my object has the following: Name = {0}, Number = {1}, Date = {2}, Salary = ${3}", _name, _number, _date, _salary);
}

Answer 3

Rather try something like

public override string ToString()
{
    return String.Format("Name : {0}, number {1}, date {2}, salary {3}",_name,_number,_date,_salary);
}

But it neads to be part of the class

so

class Employee
{
    private string _name;
    private string _number;
    private int _date;
    private int _salary;

    .....

    public override string ToString()
    {
        return String.Format("Name : {0}, number {1}, date {2}, salary {3}",_name,_number,_date,_salary);
    }
}

Have a look at String.Format Method

Replaces each format item in a specified string with the text equivalent of a corresponding object's value.

Answer 4

If you are using C# 6 (or later) use the nameof() method for the property names in the string in case the property names change. You can also use the $"" notation instead of using string.Format() .

For example:

public override string ToString()
{
    return $"{nameof(Name)}: {_name}";
}

Answer 5

You could try to format the output in a nice format. (not tested, though)

public override string ToString()
{
    return string.Format("Name: {0} Number: {1:n0} Date: {2:yyyy-MM-dd} Salary: {3:n2}", _name, _number, _date, _salary);
}

there are a lot of purposes overwriting .ToString(), depending on the context. for example,

• some developers like to have nicely formatted object description when doing debug, overwriting .ToString() would allow them to have meaningful description with some identifier (for example, the Id of a object);
• Some developers like to put some serialization code into the ToString() method;
• Some developers even put some debug code into the .ToString() method, though it might not be a good practice.

it really depending on the context of your needs. you may find some good practices to follow online - believe there are plenty of resources online.

Answer 6

Without overiding ToString, if you tried to "get" the string value of an Employee, eg

var employee1= new Employee(); Console.WriteLine(employee1);

What you'd get is:

ConsoleApplication1.Program+Employee

Which provides no information at all to help you (or a UI) display relevant information.

I use return _name + _number + _date + _salary; Which defaults to string,

or a more verbose

return "Name:" + _name + " Number:" + _number + " etc...";

Answer 7

class Program
{
    static void Main( )
    {
        int Number = 10;
        Console.WriteLine(Number.ToString());

        Customer cc = new Customer();
        cc.FirstName = "Rakibuz";
        cc.LastName = "Sultan";

        Console.WriteLine(Convert.ToString(cc));

    }
}

public class Customer
{
    public string FirstName;
    public string LastName;

    public override string ToString()
    {
        return FirstName + " " + LastName;
    }

}