PHP / MySQL —是什么|| 意思？

Question

I am trying to set up a simple php/mysql database on my website and the example has a line that says:

 if (!$searchtype || !?searchterm) {

What are the ||??? I tried to copy and paste them but they cause syntax errors. Noob question I know, but would love an answer nonetheless!

Answer 1

its ||(OR) logical operator

$a || $b Or TRUE if either/both $a or $b is TRUE.

and it should be

if (!$searchtype || !searchterm) {

as in op this Comment you can write this by

Answer 2

I think the code actually is :

 if (!$searchtype || !$searchterm) {

|| means OR operator, meaning conditions is satisfied if either of the condition is true.

Answer 3

Its an OR logical operator for handling conditions:

Ex :

$a || $b

Or TRUE if either $a or $b is TRUE.

See : http://php.net/manual/en/language.operators.logical.php

for more details