Question

无论如何，我可以知道哪种情况已经过去了。

if ( a || b ){
    //do common operations to both

    if (a){
    //do a operation
    }
     if (b) {
      //do be operation
    }
}

感觉就像我在内心条件下做同样的事情。怎么可以避免这样做？有没有办法知道哪个条件通过并继续进行。有些事情..

if ( a || b ){
        //do common operations to both

        if first condition was passed{
        //do a operation
        }
        if second condition was passed{
          //do b operation
        }
    }

某些操作很昂贵，不必要地重复。感谢。

Answer 1

如果在条件/表达式检查时指定值。你可以很容易地知道哪个条件通过并继续进行。

$a = 5; //true
$b = 0; //false

if ( $a_t = $a || $b_t= $b ){
    //do common operations to both
    $both = $a+$b;
    if ($a_t){
    //do a operation
        $a = $a+5;
    }
     if ($b_t) {
         $b = $b+5;
      //do be operation
    }
}
echo "a=$a & b= $b & both=$both";

修改：它也适用于isset()

$a = 5; //true
$b = 0; //false

if ( $a_t = isset($a) || $b_t= isset($b) ){
    //do common operations to both
    $both = $a+$b;
    if ($a_t){
    //do a operation
        $a = $a+5;
    }
     if ($b_t) {
         $b = $b+5;
      //do be operation
    }
}
echo "a=$a & b= $b & both=$both";

确定在PHP中传递了哪个条件

1 个答案: