Conversion operators allow us to write following code:
Money m = 121.55m;
This is basically custom conversion from decimal to Money type. It’s C# basics available since its inception - but honestly, I had to look it up. I believe it’s very rarely used and I don’t remember when I last saw a piece of code using this technique. Custom conversion are implemented as class operator and they need to be declared as static. Keywords explicit and implicit are controlling if we have to use casting or not.
For example:
public class Money
{
public decimal Amount;
public Money(decimal amount)
{
Amount = amount;
}
// explicit decimal to Money conversion operator
public static explicit operator Money(decimal d)
{
return new Money(d);
}
// implicit Money to decimal conversion operator
public static implicit operator decimal(Money m)
{
return m.Amount;
}
}
class Program
{
static void Main(string[] args)
{
decimal a = 121.55m;
// explicit conversion
Money b = (Money)a;
// implicit conversion - no cast needed
decimal c = b;
}
}