C# Online Compiler | .NET Fiddle

using System;
using static System.Math;
using Env = System.Environment;
					
public class Program
{
	public static void Main()
	{
		Console.WriteLine("Measurement with Parameterless Constrcutor");
		
		
		var m1 = new Measurement();
		Console.WriteLine(m1);
		
		var m2 =  default(Measurement);
		Console.WriteLine(m2);
		
		var m3 = new Measurement[2];
		Console.WriteLine(string.Join(", ", m3));
		

		Console.WriteLine("");
		Console.WriteLine("Measurement Without Explicit Constructor and Auto Initializer");
		
		var mwoc1 = new MeasurementWithoutConstructor();
		Console.WriteLine(mwoc1);
		
		var mwoc2 = default(MeasurementWithoutConstructor);
		Console.WriteLine(mwoc2);
		
		Console.WriteLine("");
		Console.WriteLine("Measurement With Explicit Constructor and Auto Initializer");
		
		var mwc1 = new MeasurementWithConstructor();
		Console.WriteLine(mwc1);
		
		var mwc2 = new MeasurementWithConstructor(5);
		Console.WriteLine(mwc2);
		
		var mwc3 = default(MeasurementWithConstructor);
		Console.WriteLine(mwc3);
		
	}
	
	public struct Measurement
	{
		public double Value {get; set;}
		public string Description {get; set;}
		
		public Measurement() {
			Value = 5;
			Description = "Measurment";
		}
		
		public override string ToString() => $"Value: {Value}, Description: ({Description})";
	}
		
	public struct MeasurementWithoutConstructor
	{
		public double Value {get; set;}
		public string Description {get; init;} = "Measurement";
		
		public override string ToString() => $"Value: {Value}, Description: ({Description})";
	}

	public struct MeasurementWithConstructor
	{
		public double Value {get; set;}
		public string Description {get; init;} = "Measurement";
		
		//uncomment this for auto property initializers to work
		public MeasurementWithConstructor() {
			Value = 1;
		}
		
		public MeasurementWithConstructor(double value) {
			Value = value;
		}
		
		public override string ToString() => $"Value: {Value}, Description: ({Description})";
	}
	
}

 
using System;
using static System.Math;
using Env = System.Environment;
                    
public class Program
{
    public static void Main()
    {
        Console.WriteLine("Measurement with Parameterless Constrcutor");
        
        
        var m1 = new Measurement();
        Console.WriteLine(m1);
        
        var m2 =  default(Measurement);
        Console.WriteLine(m2);
        
        var m3 = new Measurement[2];
        Console.WriteLine(string.Join(", ", m3));
        
​
        Console.WriteLine("");
        Console.WriteLine("Measurement Without Explicit Constructor and Auto Initializer");
        

Compilation error (line 58, col 16): A 'struct' with field initializers must include an explicitly declared constructor.