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PHP - Manual: array_count_values

2024-03-29

array_count_values

(PHP 4, PHP 5, PHP 7, PHP 8)

array_count_values统计数组中所有的值

说明

array_count_values(array $array): array

array_count_values() 返回一个数组: 数组的键是 array 里单元的值; 数组的值是 array 单元的值出现的次数。

参数

array

统计这个数组的值

返回值

返回一个关联数组,用 array 数组中的值作为键名,该值在数组中出现的次数作为值。

错误/异常

对数组里面的每个不是 stringint 类型的元素抛出一个警告错误(E_WARNING)。

范例

示例 #1 array_count_values() 例子

<?php
$array 
= array(1"hello"1"world""hello");
print_r(array_count_values($array));
?>

以上例程会输出:

Array
(
    [1] => 2
    [hello] => 2
    [world] => 1
)

参见

add a noteadd a note

User Contributed Notes 6 notes

up
15
sergolucky96 at gmail dot com
4 years ago
Simple way to find number of items with specific values in multidimensional array:

<?php

$list
= [
  [
'id' => 1, 'userId' => 5],
  [
'id' => 2, 'userId' => 5],
  [
'id' => 3, 'userId' => 6],
];
$userId = 5;

echo
array_count_values(array_column($list, 'userId'))[$userId]; // outputs: 2
?>
up
4
szczepan.krolgmail.c0m
12 years ago
Here is a Version with one or more arrays, which have similar values in it:
Use $lower=true/false to ignore/set case Sensitiv.

<?php

$ar1
[] = array("red","green","yellow","blue");
$ar1[] = array("green","yellow","brown","red","white","yellow");
$ar1[] = array("red","green","brown","blue","black","yellow");
#$ar1= array("red","green","brown","blue","black","red","green"); // Possible with one or multiple Array

$res = array_icount_values ($ar1);
print_r($res);

function
array_icount_values($arr,$lower=true) {
    
$arr2=array();
     if(!
is_array($arr['0'])){$arr=array($arr);}
     foreach(
$arr as $k=> $v){
      foreach(
$v as $v2){
      if(
$lower==true) {$v2=strtolower($v2);}
      if(!isset(
$arr2[$v2])){
         
$arr2[$v2]=1;
      }else{
          
$arr2[$v2]++;
           }
    }
    }
    return
$arr2;
}
/*
Will print:
Array
(
    [red] => 3
    [green] => 3
    [yellow] => 4
    [blue] => 2
    [brown] => 2
    [white] => 1
    [black] => 1
)
*/
?>
up
2
anvil_sa at NOSPAMNO dot hotmail dot com
2 years ago
Based on sergolucky96 suggestion
Simple way to find number of items with specific *boolean* values in multidimensional array:

<?php

$list
= [
  [
'id' => 1, 'result' => true],
  [
'id' => 2, 'result' => true],
  [
'id' => 3, 'result' => false],
];
$result = true;

echo
array_count_values(array_map(function($v) {return $v?'true':'false';},array_column($list, 'result')))[$result]
// outputs: 2

?>
up
0
Dominic Vonk
8 years ago
The case-insensitive version:

<?php
function array_count_values_ci($array) {
   
$newArray = array();
    foreach (
$array as $values) {
        if (!
array_key_exists(strtolower($values), $newArray)) {
           
$newArray[strtolower($values)] = 0;
        }
       
$newArray[strtolower($values)] += 1;
    }
    return
$newArray;
}
?>
up
0
rabies dot dostojevski at gmail dot com
15 years ago
I couldn't find a function for counting the values with case-insensitive matching, so I wrote a quick and dirty solution myself:

<pre><?php
function array_icount_values($array) {
   
$ret_array = array();
    foreach(
$array as $value) {
        foreach(
$ret_array as $key2 => $value2) {
            if(
strtolower($key2) == strtolower($value)) {
               
$ret_array[$key2]++;
                continue
2;
            }
        }
       
$ret_array[$value] = 1;
    }
    return
$ret_array;
}

$ar = array('J. Karjalainen', 'J. Karjalainen', 60, '60', 'J. Karjalainen', 'j. karjalainen', 'Fastway', 'FASTWAY', 'Fastway', 'fastway', 'YUP');
$ar2 = array_count_values($ar); // Normal matching
$ar = array_icount_values($ar); // Case-insensitive matching
print_r($ar2);
print_r($ar);
?></pre>

This prints:

Array
(
    [J. Karjalainen] => 3
    [60] => 2
    [j. karjalainen] => 1
    [Fastway] => 2
    [FASTWAY] => 1
    [fastway] => 1
    [YUP] => 1
)
Array
(
    [J. Karjalainen] => 4
    [60] => 2
    [Fastway] => 4
    [YUP] => 1
)

I don't know how efficient it is, but it seems to work. Needed this function in one of my scripts and thought I would share it.
up
-2
pmarcIatIgeneticsImedIharvardIedu
19 years ago
array_count_values function does not work on multidimentional arrays.
If $score[][] is a bidimentional array, the command
"array_count_values ($score)" return the error message "Warning: Can only count STRING and INTEGER values!".

官方地址:https://www.php.net/manual/en/function.array-count-values.php

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