PHP通过增量式抛出一个变量

Question

如何传递增量的类型抛出一个变量像波纹管的例子：

function next_prev_elem($step_id, $array, $incre){ 
    foreach ($array as $i) { 
     $incre.$step_id; 
     foreach ($array as $item) { 
      if($step_id === $item['id']){ 
       return $step_id; 
       break; 
      } 
     } 
    } 
    return false; 
} 
$prev_id = next_prev_elem($id, $page_news, '--'); 
$next_id = next_prev_elem($id, $page_news, '++'); 

Answer 1

感谢@Marc B，我结束了此解决方案：

function next_prev_elem($step_id, $array, $step){ 
    foreach ($array as $i) { 
     $step_id = $step_id + $step; 
     foreach ($array as $item) { 
      if($step_id === $item['id']){ 
       return $step_id; 
       break; 
      } 
     } 
    } 
    return false; 
} 
$prev_id = next_prev_elem($id, $page_news, -1); 
$next_id = next_prev_elem($id, $page_news, 1); 

Answer 2

function next_prev_elem($step_id, $array, $incre){ 
    foreach ($array as $i) { 

     switch($incre) { 
      case '++': 
      $step_id++; 
      break; 
      case '--': 
      $step_id--; 
      break; 
     } 

     foreach ($array as $item) { 
      if($step_id === $item['id']){ 
       return $step_id; 
       break; 
      } 
     } 
    } 
    return false; 
} 

$prev_id = next_prev_elem($id, $page_news, '--'); 
$next_id = next_prev_elem($id, $page_news, '++');