仅在数组中定位数字键

php arrays

2022-08-30 20:31:55

我有一个包含2种键，字符串和整数的数组。我想在这个数组上做，并且只想对数字键做。最优雅的方法是什么？foreach()

答案 1

下面是一个复杂的方法，用于返回数字键，然后循环访问它们。array_filter()

// $input_array is your original array with numeric and string keys
// array_filter() returns an array of the numeric keys
// Use an anonymous function if logic beyond a simple built-in filtering function is needed
$numerickeys = array_filter(array_keys($input_array), function($k) {return is_int($k);});

// But in this simple case where the filter function is a plain
// built-in function requiring one argument, it can be passed as a string:
// Really, this is all that's needed:
$numerickeys = array_filter(array_keys($input_array), 'is_int');

foreach ($numerickeys as $key) {
  // do something with $input_array[$key']
}

不过，仅仅提前完成所有事情要容易得多：

foreach ($input_array as $key => $val) {
  if (is_int($key)) {
    // do stuff
  }
}

编辑误读了原始帖子，以为我看到的是“数字”而不是“整数”键。更新为使用而不是 .is_int()is_numeric()

答案 2

    foreach($array as $key => $val) {
        if(!is_int($key))
             continue;
        // rest of the logic
    }