c# boolean operators - normal vs. short-circuit

Question

question regarding BOOLEAN operator '|' and '||'. The only difference I can find between these two operators is; when using '||' the right side of the expression will not be evaluated if the left side is true.

Outside of person preference why would one use '|' over '||' for boolean testing?

if(true | false)
{
do something
}

vs 
if (true || false)
{
do something
}

Answer 1

It's primarily an issue if the operation has side effects:

Consider the following:

using(IEnumerator iterator1 = args.GetEnumerator())
using (IEnumerator iterator2 = args.GetEnumerator())
{
    while (iterator1.MoveNext() | iterator2.MoveNext())
    {
        //do stuff
    }
}

Because the MoveNext operations cause side effects it may be important for both sides of the | to be executed regardless of whether the first is true.

Answer 2

why would one use '|' over '||' for boolean testing?

If (for some reason) the right side has side-effects that you need to occur.

This is generally not good practice, however.

Answer 3

Outside of person preference why would one use '|' over '||' for boolean testing?

Precisely because you might want both sides to be evaluated. There may be side-effects which you need to occur either way.

It's rare, but it's feasible.