Why Must I Initialize All Fields in my C# struct with a Non-Default Constructor?

Question

I would like to try this code:

public struct Direction
{
   private int _azimuth;

   public int Azimuth
   {
     get { return _azimuth; }
     set { _azimu         


        

Answer 1

I just found an explanation in the MSDN forum stating that this rule is enforced because zeroing out the memory is skipped if you use a none default constructor. So you will have to provide initialization values for all fields in order to avoid some fields containing random values. You achieve this easily be calling the parameter less default constructor, but at the cost of initializing some fields twice.

I cannot tell if this explanation is correct, but it sounds reasonable.

When you define a non-default initializer, C# requires you to set all fields because it skips the zeroing of memory and lets you initialize it - otherwise you'd have to have a double initialization performance hit. If you don't care about the (very slight) performance hit you can always chain a call to the : this() initializer and then only initialize selected fields.