在IF语句中，在发现一个为真之后，条件检查是否继续（PHP）

Question

For IF statements using OR or similar operators, after one is found to be true, does PHP continue checking the rest or does it stop there? For example.

if(true == true OR a_checking_function())

Would both be checked, or would PHP just check one?

Answer 1

No, as soon as the first true is found, it goes straight to the code in the braces. If you used an 'AND' keyword, then it would check the second condition.

You may want to look at operator / logic precedence. For example, what would happen for the following conditions?:

if($a = $b AND $c = $d AND $e = $f)...
if($a = $b AND $c = $d OR $e = $f)...
if($a = $b OR $c = $d AND $e = $f)...

http://php.net/manual/en/language.operators.precedence.php