Determine whether the two array structures are consistent (the keys are consistent)

How to use PHP to determine whether the keys of two arrays are consistent?

During the development process, you often encounter situations where you need to determine whether the keys of two arrays are consistent. PHP provides many convenient functions to manipulate arrays, and there are methods that can help us determine whether the array keys are consistent. This article will introduce how to use PHP to determine whether the keys of two arrays are consistent.

Method 1: Use array_keys() and sort() functions

The array_keys() function can return all key names in the array, while the sort() function can sort the array. So we can get the key names of the two arrays first, then sort them and compare them.

 <?php
$array1 = [
    'apple' => 1,
    'banana' => 2,
    'cherry' => 3
];

$array2 = [
    'banana' => 5,
    'apple' => 1,
    'cherry' => 7
];

// Get the key name of the array
$keys1 = array_keys($array1);
$keys2 = array_keys($array2);

// Sort the key names
sort($keys1);
sort($keys2);

// Compare whether the key names of the two arrays are consistent
if ($keys1 == $keys2) {
    echo "The keys of the two arrays are consistent！";
} else {
    echo "The keys of the two arrays are inconsistent！";
}
?>

Analysis:

1. Use array_keys() to get all keys for two arrays.

2. Use sort() to sort the keyname array.

3. Compare whether the sorted key name array is consistent.

If it is consistent, it means that the keys of the two arrays are the same; if it is inconsistent, it means that the keys are different.

Method 2: Use array_diff_key() function

The array_diff_key() function is used to compare the keys of two arrays and returns keys that exist in the first array but not in the second array. If the returned result is an empty array, it means that the keys of the two arrays are consistent.

 <?php
$array1 = [
    'apple' => 1,
    'banana' => 2,
    'cherry' => 3
];

$array2 = [
    'banana' => 5,
    'apple' => 1,
    'cherry' => 7
];

// use array_diff_key Determine whether the keys are consistent
$diff1 = array_diff_key($array1, $array2);
$diff2 = array_diff_key($array2, $array1);

if (empty($diff1) && empty($diff2)) {
    echo "The keys of the two arrays are consistent！";
} else {
    echo "The keys of the two arrays are inconsistent！";
}
?>

Analysis:

1. array_diff_key($array1, $array2) returns a key that exists in $array1 but does not exist in $array2 .

2. array_diff_key($array2, $array1) returns a key that exists in $array2 but does not exist in $array1 .

3. If both results are empty arrays, it means that the keys of the two arrays are exactly the same.

Method 3: Use array_intersect_key() function

The array_intersect_key() function is used to compare the keys of two arrays and return the keys that exist in both arrays. We can judge whether the keys are consistent by comparing them with the number of keys in the original array.

 <?php
$array1 = [
    'apple' => 1,
    'banana' => 2,
    'cherry' => 3
];

$array2 = [
    'banana' => 5,
    'apple' => 1,
    'cherry' => 7
];

// Get the intersection of two array keys
$commonKeys = array_intersect_key($array1, $array2);

// Comparing the number of keys of intersection with the number of keys of the original array
if (count($commonKeys) == count($array1) && count($commonKeys) == count($array2)) {
    echo "The keys of the two arrays are consistent！";
} else {
    echo "The keys of the two arrays are inconsistent！";
}
?>

Analysis:

1. Use array_intersect_key() to get the common keys of two arrays.

2. Compare whether the number of common keys is equal to the number of keys in the original array. If equal, it means that the keys of the two arrays are consistent.

summary

In PHP, there are multiple ways to determine whether the keys of two arrays are consistent. You can choose the most suitable method according to your specific needs. If you just need to tell if the keys are the same and don't care about the order, you can use array_diff_key() or array_intersect_key() ; if you need to consider the order, using a combination of array_keys() and sort() is a good choice.

No matter which method, it can be flexibly used according to your application scenario, so as to better complete the task.