Question

请不要生气，因为我知道这是重复的问题！

我需要使用for循环将新元素添加到数组，因为我需要增加一些值才能带来新索引。

$array = [['first'=>'a', 'second'=>'b', 'third'=>'c'], ['first'=>'d', 'second'=>'e', 'third'=>'f'],['first'=>'g', 'second'=>'h', 'third'=>'i'] ];

$length = count($array);

for($i=1; $i<=$length; $i++){
    array_push($array, ["number"=>$i]);
}

var_dump($array);

和var_dump显示：

array (size=6)
  0 => 
    array (size=3)
      'first' => string 'a' (length=1)
      'second' => string 'b' (length=1)
      'third' => string 'c' (length=1)
  1 => 
    array (size=3)
      'first' => string 'd' (length=1)
      'second' => string 'e' (length=1)
      'third' => string 'f' (length=1)
  2 => 
    array (size=3)
      'first' => string 'g' (length=1)
      'second' => string 'h' (length=1)
      'third' => string 'i' (length=1)
  3 => 
    array (size=1)
      'number' => int 1
  4 => 
    array (size=1)
      'number' => int 2
  5 => 
    array (size=1)
      'number' => int 3

array(size=6)，我只需要array(size=3)。我需要在现有'number' => int 1

中使用'number' => int 2，'number' => int 3，$array

谢谢！

Answer 1

您可以使用：

$array = [['first'=>'a', 'second'=>'b', 'third'=>'c'], ['first'=>'d', 'second'=>'e', 'third'=>'f'],['first'=>'g', 'second'=>'h', 'third'=>'i'] ];

$length = count($array);

foreach($array as $k=>$v){
    $array[$k]['number']=$k+1;  
}

var_dump($array);

输出：

array(3) {
  [0]=>
  array(4) {
    ["first"]=>
    string(1) "a"
    ["second"]=>
    string(1) "b"
    ["third"]=>
    string(1) "c"
    ["number"]=>
    int(1)
  }
  [1]=>
  array(4) {
    ["first"]=>
    string(1) "d"
    ["second"]=>
    string(1) "e"
    ["third"]=>
    string(1) "f"
    ["number"]=>
    int(2)
  }
  [2]=>
  array(4) {
    ["first"]=>
    string(1) "g"
    ["second"]=>
    string(1) "h"
    ["third"]=>
    string(1) "i"
    ["number"]=>
    int(3)
  }
}

PHP-使用for循环在数组中添加新元素？

1 个答案: