What is happening in an “If(..||..)” and “If(…&&…)” construct internally?

Question

I was just wondering what happens inside of an \"if OR\" and \"if AND\". I have a feeling that it\'s just syntactic sugar to use &

Answer 1

Their VB equivalents can be more describing. || is OrElse and && is AndAlso in VB.
These are conditional operators; meaning they make the control clause - if in your case - evaluate the conditions as needed and not all of them always.

For example, in if ( a || b ) if a is true, it doesn't matter what b is; the result is true and therefore b will not get evaluated and this will result in faster execution.

This feature can be used as a null-checking mechanism too. if ( a != null && a.prop == somevalue ) will prevent a Null Reference Exception if a is null and if it's not null, its prop property will be accessed to evaluate the second condition.