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How to remove duplicate elements from PHP array using foreach loop?
How to remove duplicate elements from PHP array using foreach loop?
Apr 27, 2024 am 11:33 AM
The method of using foreach loop to remove duplicate elements in PHP array is as follows: traverse the array, if the element already exists and the current position is not the first occurrence, delete it. For example, if there are duplicate records in the database query results, you can use this method to remove them and obtain results without duplicate records.
How to remove duplicate elements from a PHP array using foreach loop?
PHP's array_unique function can be used to remove duplicate elements from an array, but sometimes you may want to do this manually using a foreach loop. Here's how to achieve this using a foreach loop:
<?php
// 創(chuàng)建一個包含重復元素的數(shù)組
$array = array(1, 2, 3, 4, 5, 1, 2, 3);
// 使用 foreach 循環(huán)遍歷數(shù)組
foreach ($array as $key => $value) {
// 如果數(shù)組中已經存在該值，則刪除它
if (array_key_exists($value, $array) && $key !== array_key_first($array)) {
unset($array[$key]);
}
}
// 輸出去除重復元素后的數(shù)組
print_r($array);
?>Practical example: Remove duplicate values ??from database query results
Suppose you have a query database and return the following results PHP script:
$results = [
['id' => 1, 'name' => 'John'],
['id' => 2, 'name' => 'Mary'],
['id' => 1, 'name' => 'John'], // 重復的記錄
['id' => 3, 'name' => 'Bob'],
];You can use the above foreach loop to remove duplicate values ??and get the following result:
$uniqueResults = [
['id' => 1, 'name' => 'John'],
['id' => 2, 'name' => 'Mary'],
['id' => 3, 'name' => 'Bob'],
];The above is the detailed content of How to remove duplicate elements from PHP array using foreach loop?. For more information, please follow other related articles on the PHP Chinese website!
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