php variable as conditional assignment

问题

I was wondering how can I asign a conditional assignment to a php variable and use it inside other conditional, like this:

$cndtnal='&& $x==4'

if($y==5 $cndtnal){
   print 'Hello World';
}

Thanks.

回答1:

You should try avoiding the use of eval as much as possible, but if you want to use it, then you could do:

$cndtnal='&& $x=4';
if($y==5 .eval("return '$cndtnal';")  ){
   echo 'Hello World';
}
else {
    echo "this";
}

来源：https://stackoverflow.com/questions/12170527/php-variable-as-conditional-assignment