Why writing items to console writes only namespace and class name instead of data? [duplicate]

Answer 1

You are using this overload of WriteLine:

public static void WriteLine(object value)

and this overload call ToString method of parameter to produce its string representation. As mentioned Here the default implementation of ToString returns the fully qualified name of the type.

You can override ToString in your City class to be able use instances of this type where a string is expected like Console.WriteLine

public override string ToString()
{
   return CityName + Temperature.ToString(); 
   // return $"{CityName} : {Temperature}"; // Or use C# string interpolation
}

Or directly produce required string and pass that to WriteLine method:

Console.WriteLine($"{item.CityName} : {item.Temperature});

Answer 2

You are passing object to the Console.WriteLine(item) instead of passing the string. Console.WriteLine invokes ToString() method of that object that by default returns namespace+class name. You can override this behavior like next:

    public class City //class
    {
        public string CityName { get; set; }
        public int Temperature { get; set; }

        public City(string name, int temp)//konstruktor 
        {
            this.CityName = name;
            this.Temperature = temp;
        }

        public override string ToString()
        {
            return string.Format("{0} {1}", CityName, Temperature);
        }

    }

Or you can use another overload of WriteLine method:

Console.WriteLine("{0} {1}", item.CityName, item.Temperature);

Answer 3

Change Console.WriteLine(item); to one of the following options, if you simply want to write out the contents of your City object.

Console.WriteLine("City: " + item.CityName + " has a temperature of " + item.Temperature + " degrees.");

or, you can use string.Format if you prefer:

Console.WriteLine(string.Format("City: {0} has a temperature of {1} degrees.", item.CityName, item.Temperature));

Answer 4

Here you are trying to print the object itself. If you would like to print the CityName and Temperature, inside the foreach you have to print the property.

foreach (var item in cityList)
    {
        Console.WriteLine(item.CityName);
        Console.WriteLine(item.Temperature);
    }

But here, you are getting a single city and temperature only and printing it. Why do you need a list in that case?

Answer 5

The item in cityList is of City type, which means that you have properties for CityName and Temperature.

You should use:

Console.WriteLine(item.CityName + " is at " + item.Temperature + ".");

or something similar.