Different values ​​of two arrays in php

In PHP development, it is often necessary to compare different values ​​in two arrays. When we need to operate by comparing the values ​​in two arrays, we need to find the different values ​​in the two arrays. This article will explain how to find out the different values ​​in two arrays in PHP and provide sample code.

Method 1: array_diff function

The array_diff function can be used to find different values ​​in two arrays. This function can accept two or more arrays as parameters and returns a new array containing values ​​that exist in the first array but not in the other arrays.

The syntax of this function is as follows:

array array_diff (array $array1 , array $array2 [, array $... ])

Among them, $array1 means we need The first array compared, $array2 and subsequent parameters represent other arrays that need to be compared with $array1.

The following is a simple example code that creates two arrays and uses the array_diff function to find out the different values ​​in the two arrays:

$arr1 = array("apple", "banana", "orange");
$arr2 = array("banana", "orange", "pear");
$result = array_diff($arr1, $arr2);
print_r($result);

After running the code, the results are output As:

Array ( [0] => apple )

As you can see, this code compares two arrays $arr1 and $arr2, and outputs different values ​​(i.e. "apple" in $arr1).

Method 2: array_unique function

Another way to find out the different values ​​in two arrays is to use the array_unique function. This function can remove duplicate values ​​from an array and return a new array after removing duplicate values. We can find the different values ​​in two arrays by using the array_unique function and array_merge function.

The following is a sample code that uses the array_unique function and array_merge function:

$arr1 = array("apple", "banana", "orange");
$arr2 = array("banana", "orange", "pear");
$arr3 = array_merge($arr1, $arr2);
$result = array_diff($arr3, array_unique($arr3));
print_r($result);

After running the code, the output result is:

Array ( [0] => banana [1] => orange )

As you can see, the code first uses The array_merge function merges $arr1 and $arr2 together, then uses the array_unique function to remove duplicate values, and finally uses the array_diff function to find out the different values ​​and output them.

Method 3: foreach loop

Another way to find out the different values ​​in two arrays is to use a foreach loop. This method iterates through two arrays and stores different values ​​into the new array.

The following is a sample code that uses a foreach loop to find different values:

$arr1 = array("apple", "banana", "orange");
$arr2 = array("banana", "orange", "pear");
$result = array();

foreach ($arr1 as $value) {
    if (!in_array($value, $arr2)) {
        $result[] = $value;
    }
}

foreach ($arr2 as $value) {
    if (!in_array($value, $arr1)) {
        $result[] = $value;
    }
}

print_r($result);

After running the code, the output result is:

Array ( [0] => apple [1] => pear )

As you can see, the code first Traverse $arr1 and store different values ​​into the $result array, then traverse $arr2 and store different values ​​into the $result array.

To sum up, we can use various methods such as array_diff function, array_unique function and foreach loop to find out the different values ​​in two arrays. In actual development, we can choose the appropriate method according to different situations.

The above is the detailed content of Different values ​​of two arrays in php. For more information, please follow other related articles on the PHP Chinese website!