How to remove an element from an array in php

php method to remove an element from an array: 1. Use unset to delete after traversing through foreach; 2. Use array_flip and unset to delete; 3. Search and delete through array_search; 4. Search and specify by using array_keys The value can be recycled and unset.

The operating environment of this article: Windows 7 system, PHP version 7.1, DELL G3 computer

How to remove an element from an array in php

The example in this article describes PHP deleting elements with specified values ​​​​in the array.

The test array is as follows:

//这是一个测试数组
$testArr = array(
  't' => 'qq',
  'q' => 'qq',
  'b' => 'baidu',
  'a' => 'ali',
  'm' => 'xiaomi'
);

Method one:

//foreach遍历后unset删除,这种方法也是最容易想到的方法
function delByValue($arr, $value){
  if(!is_array($arr)){
    return $arr;
  }
  foreach($arr as $k=>$v){
    if($v == $value){
      unset($arr[$k]);
    }
  }
  return $arr;
}

Test:

$testArr = delByValue($testArr,'baidu');
print_r($testArr)

Running result:

Array
(
    [t] => qq
    [q] => qq
    [a] => ali
    [m] => xiaomi
)

Method two:

//array_flip之后unset,这种方法有一个弊端，就是反转后由于有两个键值都为qq，有一个数据将会丢失，所以在使用时请谨慎）
function delByValue($arr, $value){
  $tempArr = array_flip($arr);
  unset($tempArr[$value]);
  return array_flip($tempArr);
}

Test:

$testArr = delByValue($testArr,'baidu');
print_r($testArr)

Running result:

Array
(
    [q] => qq
    [a] => ali
    [m] => xiaomi
)

Method three:

//array_search,这种方法亦有弊端，array_search搜索到一个合适的值时便返回，所以在数组存在多个相关的值这种方法不适用）
function delByValue($arr, $value){
  $key = array_search($value,$arr);
  if(isset($key)){
    unset($arr[$key]);
  }
  return $arr;
}

Test:

$testArr = delByValue($testArr,'baidu');
print_r($testArr)

Running result:

Array
(
    [t] => qq
    [q] => qq
    [a] => ali
    [m] => xiaomi
)

Method 4:

//使用array_keys搜索指定的值再循环unset）
function delByValue($arr, $value){
  $keys = array_keys($arr, $value);
  var_dump($keys);
  if(!empty($keys)){
    foreach ($keys as $key) {
      unset($arr[$key]);
    }
  }
  return $arr;
}

Test:

$testArr = delByValue($testArr,'baidu');
print_r($testArr)

Running result:

array(1) {
  [0]=>
  string(1) "b"
}
Array
(
    [t] => qq
    [q] => qq
    [a] => ali
    [m] => xiaomi
)

Summarizing the four methods, the more feasible methods are Method 1 and Method 4. , As for which of these two methods is better, it should be analyzed in detail according to the specific situation.

Recommended learning: "PHP Video Tutorial"

The above is the detailed content of How to remove an element from an array in php. For more information, please follow other related articles on the PHP Chinese website!