Extraction steps: 1. Use the array_count_values() function to count the number of occurrences of elements in the array. The syntax "array_count_values (original array)" will return an associative array whose key name is the value of the original array. The key value is the number of times the value appears in the original array; 2. Use the array_keys() function to obtain the element with the number of occurrences 1, that is, extract the key name of the element with the key value 1 in the associative array, the syntax "array_keys(associative array ,1)".
The operating environment of this tutorial: windows7 system, PHP version 8.1, DELL G3 computer
In PHP, you can use the array_count_values() function and array_keys() function to extract unique values in the array.
Implementation steps:
Step 1: Use the array_count_values() function to count the number of occurrences of elements in the array
array_count_values( ) function can count the number of occurrences of all values in the array; will return an associative array, the key name of its element is the value of the original array, and the key value is the number of times the value appears in the original array
.
<?php header('content-type:text/html;charset=utf-8'); $arr=array(1,"A","Cat",2,"Dog","A",3,4,5,5,3,1); echo "原数组"; var_dump($arr); $con=array_count_values($arr); echo "各数组元素的出现次数:"; var_dump($con); ?>
Step 2: Use the array_keys() function to extract unique values in the array
Values with a count of 1, Just don't repeat the value.
Just use the array_keys() function to get the key name corresponding to the element with a key value of 1 in the returned associative array.
<?php header('content-type:text/html;charset=utf-8'); $arr=array(1,"A","Cat",2,"Dog","A",3,4,5,5,3,1); echo "原数组"; var_dump($arr); $con=array_count_values($arr); echo "各数组元素的出现次数:"; var_dump($con); $res=array_keys($con,1); echo "数组中的不重复值:"; var_dump($res); ?>
Description:
array_key() function can get some or all key names in the array
array_keys($array [, $search_value = null [, $strict = false]])
Parameter description is as follows:
===
. array_keys() function will return the obtained array key name in the form of an array.
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