Question

Im trying to test a validation using an if statement.

if (($red == "1") && ($blue = "1") ) { $green = "hello"; }

Before this statement runs $blue = 0.

After i run this… $blue changes to 1.

Any ideas why?

Answer 1

You are using = in place of ==:

if (($red == "1") && ($blue = "1") ) { $green = "hello"; }
                           ^^^

As a result (assuming the left side of && returns true) $blue gets assigned "1".

It’s one of the most common programming mistakes!! As a way to prevent it from happening programmers put the constant on the left hand side of the the == as:

1 == $blue

so that if by mistake you end up writing = in place of == :

1 = $blue

you get a syntax error as you cannot assign to a constant.