Why null == myVar instead of myVar == null? [duplicate]

Question

Possible Duplicate:
Why does one often see “null != variable” instead of “variable != null” in C#?

I see it from times to times and I'd like to know why. Is there any difference at all?

Answer 1

It's an old habit to avoid the accidental typo of myVar = null (whoops). It's still helpful in some languages, but C# will protect you from doing it, so it's not necessary there.

Answer 2

It's a holdover from C where older compilers would not catch this:

if (foo = null)

when you mean this:

if (foo == null)

The classic joke example is this mistake:

if (fireTheNukes = true)
    fireTheNukes();

This is generally accepted as an archaic pattern as any compiler worth its salt will catch an assignment within a conditional statement. I would avoid this pattern in your code as it serves no purpose these days.