问题
I seem to have a small problem, in the code below $a_trip is always true, even if $trip!= $admin_trip. Any idea why?
if($trip == $admin_trip)
$a_trip = true;
if($a_trip == true)
$trip = ("~::##Admin##::~");
回答1:
In PHP, strings and numbers other than zero will evaluate as true. Make sure that $a_trip is false or empty, or use the equality operator that evaluates type:
if($a_trip === true)
回答2:
PHP's normal equality is very lax, and considers many values to be the same even when types are different.
回答3:
Beat me to it. === means 'identical'.
Check this out.
http://php.net/manual/en/language.operators.comparison.php
Also a sidenote, you should use { } in your if statements. You'll thank yourself later when debugging. It's easier to read.
来源：https://stackoverflow.com/questions/2485506/php-boolean-help