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using System;

public class Program
{
	private const bool ShowAnswer = true;

	public static void Main()
	{
		// homework: 
		// 1. put the method calls in order of byte size
		// 2. fill in the comment with the byte size
		MeasureBytes<decimal>(); // 
		MeasureBytes<byte>(); // 
		MeasureBytes<short>(); // 
		MeasureBytes<double>(); // 
		MeasureBytes<int>(); // 
		MeasureBytes<Dimensions>(); // 
		MeasureBytes<Address>(); // 
		MeasureBytes<DimensionsUnit>(); // 
		MeasureBytes<long>(); // 
		MeasureBytes<DateTime>(); // 
		MeasureBytes<DimensionsBigger>(); // 
	}

	// http://stackoverflow.com/a/207605/1108891
	public static void MeasureBytes<T>()where T : new ()
	{
		// You should probably create a single instance beforehand 
		// to make sure that no new JITted code contributes to the number
		var x = new T();
		
		// use GC.GetTotalMemory for a base point
		var forceFullCollection = true;
		var initialBytes = GC.GetTotalMemory(forceFullCollection);
		
		// create a big array
		var size = 10000;
		var array = new T[size];
		
		// fill the array with references to new instances of your type
		for (var i = 0; i < array.Length; i = i + 1)
		{
			array[i] = new T();
		}

		// and then call GetTotalMemory again
		var finalBytes = GC.GetTotalMemory(forceFullCollection);
		
		// Take one value away from the other, 
		// and divide by the number of instances
		var difference = finalBytes - initialBytes;
		var bytesPerInstance = difference / size;
	
		if (ShowAnswer)
		{
		    Console.WriteLine($"An instance of {array[0].GetType()} is {bytesPerInstance} bytes.");
		}
	}
}

public enum DimensionsUnit
{
	Centimeters,
	Inches
}

public struct Dimensions
{
	public readonly short Height;
	public readonly short Width;
	public readonly short Length;
	public readonly DimensionsUnit Units;
}

public struct DimensionsBigger
{
	public readonly decimal Height;
	public readonly decimal Width;
	public readonly decimal Length;
	public readonly string Units;
}

public struct Address
{
	public readonly string AddressLineOne;
	public readonly string AddressLineTwo;
	public readonly string PostalCode;
	public readonly string City;
	public readonly string Province;
	public readonly string Country;
}

            Console.WriteLine($"An instance of {array[0].GetType()} is {bytesPerInstance} bytes.");
 
using System;
​
public class Program
{
    private const bool ShowAnswer = true;
​
    public static void Main()
    {
        // homework: 
        // 1. put the method calls in order of byte size
        // 2. fill in the comment with the byte size
        MeasureBytes<decimal>(); // 
        MeasureBytes<byte>(); // 
        MeasureBytes<short>(); // 
        MeasureBytes<double>(); // 
        MeasureBytes<int>(); // 
        MeasureBytes<Dimensions>(); // 
        MeasureBytes<Address>(); // 
        MeasureBytes<DimensionsUnit>(); // 
        MeasureBytes<long>(); // 
        MeasureBytes<DateTime>(); // 
        MeasureBytes<DimensionsBigger>(); // 
    }
​

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