Question

I’m facing the problem that C# in my case can’t cast the number 1 to bool. In my scenario (bool)intValue doesn’t work. I get an InvalidCastException. I know I can use Convert.ToBoolean(...) but I’m just wondering it doesn’t work. Any explanation for this?

My code is

if (actualValueType.Name == "Boolean" || setValueType.Name == "Boolean")
{
   if ((bool)actualValue != (bool)setValue)
   ...
}

Answer 1

int and bool can’t be converted implicitly (in contrast to C++, for example).

It was a concious decision made by language designers in order to save code from errors when a number was used in a condition. Conditions need to take a boolean value explicitly.

It is not possible to write:

int foo = 10;

if(foo) {
  // Do something
}

Imagine if the developer wanted to compare foo with 20 but missed one equality sign:

if(foo = 20) {
  // Do something
}

The above code will compile and work – and the side-effects may not be very obvious.

Similar improvements were done to switch: you cannot fall from one case to the other – you need an explicit break or return.