How to remove duplicate elements from an array in php

php method to remove duplicate elements in an array: first create a PHP sample file; then define an "array_remove_value" method; then delete it through unset and other functions; finally use the key before deleting the array to operate the corresponding Just value.

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Method 1. Completely delete duplicate array instances-----Delete An element in the array

function array_remove_value(&$arr, $var){
foreach ($arr as $key => $value) {
if (is_array($value)) {
array_remove_value($arr[$key], $var);
} else {
$value = trim($value);
if ($value == $var) {
unset($arr[$key]);
} else {
$arr[$key] = $value;
}
}
}
}

$a is an array:

count($a); //得到4
unset($a[1]); //删除第二个元素
count($a); //得到3
echo $a[2]; //数组中仅有三个元素,本想得到最后一个元素,但却得到blue,
echo $a[1]; //无值
?>

That is to say, after deleting the elements in the array, the number of elements in the array (obtained with count()) becomes , but the array subscripts are not rearranged, and the corresponding value must be manipulated using the key before deleting the array.

Later I adopted another method. In fact, it was not called a "method" at all. I used the ready-made function array_splice() in php4.

count ($a); //得到4
array_splice($a,1,1); //删除第二个元素
count ($a); //得到3
echo $a[2]; //得到yellow
echo $a[1]; //得到blue
?>

Method 2. Function to delete duplicate elements in an array

function delmember(&$array, $id)
{
$size = count($array);
for($i = 0; $i <$size - $id - 1; $i ++)
{
$array[$id + $i] = $array[$id + $i + 1];
}
unset($array[$size - 1]);
}

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