PHP - 計數特定數組值

Question

如何計算數組中等於常量的元素數？ 例如，

$myArray = array("Kyle","Ben","Sue","Phil","Ben","Mary","Sue","Ben"); 

我怎麼能直接知道「奔」是多少裏面？

Answer 1

$array = array("Kyle","Ben","Sue","Phil","Ben","Mary","Sue","Ben"); 
$counts = array_count_values($array); 
echo $counts['Ben']; 

Answer 2

使用array_count_values()函數。檢查此鏈接http://php.net/manual/en/function.array-count-values.php

Answer 3

嘗試array_count_values（）函數

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

輸出：

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

http://php.net/manual/en/function.array-count-values.php

Answer 4

使用array_count_values功能。

$ countValues = array_count_values（$ myArray）;

echo $countValues["Ben"];

Answer 5

嘗試PHP函數array_count_values。

Answer 6

您可以使用array_keys和count。

$array = array("blue", "red", "green", "blue", "blue"); 
echo count(array_keys($array, "blue")); 

輸出：

3 

Answer 7

如果要算上陣列內所有相同的出現次數，這裏有一個函數來計算它們，並將結果作爲多維數組的形式返回：

function countSame($array) { 

$count = count($array); 
$storeArray = array(); 
while ($count > 0) { 
$count--; 

if ($array[$count]) { 
$a = $array[$count]; 
$counts = array_count_values($array); 
$counts = $counts[$a]; 
$tempArray = array($a, $counts); 
array_push($storeArray, $tempArray); 

$keys = array_keys($array, $a); 
foreach ($keys as $k) { 
unset($array[$k]); 
} //end of foreach ($keys as $k) 
} //end of if ($array[$count]) 

} //end of while ($count > 0) 

return $storeArray; 

} //end of function countSame($array) 

Answer 8

define('SEARCH_STRING', 'Ben'); 

$myArray = array("Kyle","Ben","Sue","Phil","Ben","Mary","Sue","Ben"); 

$count = count(array_filter($myArray,function($value){return SEARCH_STRING === $value;})); 

echo $count, "\n"; 

輸出：

3 

Answer 9

array_count_values僅適用於整數和字符串。如果你碰巧要浮法/數值計數（和你是不顧精度或表示小的變化），這工作：

function arrayCountValues($arr) { 
    $vals = []; 
    foreach ($arr as $val) { array_push($vals,strval($val)); } 
    $cnts = array_count_values($vals); 
    arsort($cnts); 
    return $cnts; 
} 

注意，我回到$cnts與鍵爲字符串。這很容易重新生成它們，但我試圖確定模式的值，所以我只需要重新轉換第一個（幾個）值。

我測試了一個循環版本，創建了一個計數數組而不是使用array_count_values，結果證明效率更高（大概8-10％）！