Как найти совпадения в двух массивах

<?php

$array1

= array(2, 4, 6, 8, 10, 12);
$array2 = array(1, 2, 3, 4, 5, 6);var_dump(array_intersect($array1, $array2));
var_dump(array_intersect($array2, $array1));?>

yields the following:

array(3) {
  [0]=> int(2)
  [1]=> int(4)
  [2]=> int(6)
}

array(3) {
  [1]=> int(2)
  [3]=> int(4)
  [5]=> int(6)
}

This makes it important to remember which way round you passed the arrays to the function if these keys are relied on later in the script.

<?php
                                        //  $a = 1 2 3 4
    $union =                            //  $b =   2   4 5 6
        array_merge(
            array_intersect($a, $b),    //         2   4
            array_diff($a, $b),         //       1   3
            array_diff($b, $a)          //               5 6
        );                              //  $u = 1 2 3 4 5 6
?>

<?php
array_intersect(array(1,2,2),array(1,2,3)); //=> array(1,2,2)
array_intersect(array(1,2,3),array(1,2,2)); //=> array(1,2)
?>

$full=call_user_func_array('array_intersect', $any_number_of_arrays_here);

<?php

$orders_today

[0] = array('John Doe', 'PHP Book');
$orders_today[1] = array('Jack Smith', 'Coke');$orders_yesterday[0] = array('Miranda Jones', 'Digital Watch');
$orders_yesterday[1] = array('John Doe', 'PHP Book');
$orders_yesterday[2] = array('Z? da Silva', 'BMW Car');?>

and wants to know if the same person bought the same thing today and yesterday and use array_intersect($orders_today, $orders_yesterday) you'll get as result:

<?phpArray
(
    [0] => Array
        (
            [0] => John Doe
            [1] => PHP Book
        )

    [

1] => Array
        (
            [0] => Jack Smith
            [1] => Coke
        )

)

?>

but we can get around that by serializing the inner arrays:
<?php

$orders_today

[0] = serialize(array('John Doe', 'PHP Book'));
$orders_today[1] = serialize(array('Jack Smith', 'Coke'));$orders_yesterday[0] = serialize(array('Miranda Jones', 'Digital Watch'));
$orders_yesterday[1] = serialize(array('John Doe', 'PHP Book'));
$orders_yesterday[2] = serialize(array('Z? da Silva', 'Uncle Tungsten'));?>

so that array_map("unserialize", array_intersect($orders_today, $orders_yesterday)) will return:

<?phpArray
(
    [0] => Array
        (
            [0] => John Doe
            [1] => PHP Book
        )

)

?>

showing us who bought the same thing today and yesterday =)

[]s

<?php

$m

= range(1,1000000);
  $s = [2,4,6,8,10];// Use array_intersect to return all $m values that are also in $s
  $tstart = microtime(true);
  print_r (array_intersect($m,$s));
  $tend = microtime(true);
  $time = $tend - $tstart;
  echo "Took $time";// Use array_flip and isset to return all $m values that are also in $s
  $tstart = microtime(true);
  $f = array_flip($s);
/* $f now looks like this:
(
    [2] => 0
    [4] => 1
    [6] => 2
    [8] => 3
    [10] => 4
)
*/
// $u will hold the intersected values
  $u = [];
  foreach ($m as $v) {
    if (isset($f[$v])) $u[] = $v;
  }
  print_r ($u);
   $tend = microtime(true);
  $time = $tend - $tstart;
  echo "Took $time";
?>

Results:

Array
(
    [1] => 2
    [3] => 4
    [5] => 6
    [7] => 8
    [9] => 10
)
Took 4.7170009613037
(
    [0] => 2
    [1] => 4
    [2] => 6
    [3] => 8
    [4] => 10
)
Took 0.056024074554443

array_intersect: 4.717
array_flip+isset: 0.056

<?php

function array_intersect_fixed($array1, $array2) {

    $result = array();

    foreach ($array1 as $val) {

      if (($key = array_search($val, $array2, TRUE))!==false) {

         $result[] = $val;

         unset($array2[$key]);

      }

    }

    return $result;

}

?>

$array1 = array(true,2);
$array2 = array(1, 2, 3, 4, 5, 6);

var_dump(array_intersect($array1, $array2));

result is :
array(2) {
        [0] =>  bool(true)
        [1]  =>  int(2)
}

<?
$base= array('one', 'two', 'three');

$tosort= array('a'=>'two', 'b'=>'three', 'c'=>'five', 'd'=>'one', 'and'=>'four', 'f'=>'one');

uasort($tosort, function($key1, $key2) use ($base) {
  $a1=array_search($key1, $base);
  $a2=array_search($key2, $base);

  if ( $a1===false && $a2===false ) { return 0; }
  else if ( $a1===false && $a2 !== false) { return 1; }
  else if ( $a1!==false && $a2 === false) {return -1;}

  if( $a1 > $a2 ) { return 1; }
  else if ( $a1 < $a2 ) { return -1; }
  else if ( $a1 == $a2 ) { return 0; }       
});
var_dump($tosort);
/*
the resulting of $tosort
array
  'd' => string 'one' (length=3)
  'f' => string 'one' (length=3)
  'a' => string 'two' (length=3)
  'b' => string 'three' (length=3)
  'c' => string 'five' (length=6)
  'e' => string 'four' (length=7)
*/
Gabriel
?>

But it is not needed!  See below.

<?php
                                        //  $a = 1 2 3 4
    $union =                            //  $b =   2   4 5 6
        array_merge(
            $a,   
            array_diff($b, $a)          //               5 6
        );                              //  $u = 1 2 3 4 5 6
?>

You get the same result with $a + $b.

N.B. for associative array the results of $a+$b and $b+$a are different, I think array_diff_key is used.

Cheers, E

<?php declare(strict_types=1)$_params = ['cust_id','prod_id'];
$_params_check = array_intersect(array_keys($_GET),$_params);
if(count($_params_check) !== count($_params)) {
    header("HTTP/1.1 400 Bad Request");
    die();
}
?>

the file will die with a 400 error if cust_id or prod_id or both are missing from $_GET. But i could be used on $_POST and $_REQUEST as  well obviously.

<?php

$a = array('one', 'two', 'three', 'four', 'five', 'six', 'seven', 'height', 'nine', 'ten');

$b = array('four', 'one', 'height', 'five')

var_dump(array_intersect($a, $b);

?>



will output:

0 => 'one'

1 => 'four'

2 => 'five'

3 => 'height'

i hope this can help...

If you wish to change this. I sugest that you do this.
It simply "ignores" empty arrays. Before loop use 1st array.

<?php

$a

= array();
$a[] = 1;
$a[] = 2;
$a[] = 3;$b = array();
$b[] = 4;
$b[] = 5;
$b[] = 1;$c = array();
$c[] = 1;
$c[] = 5;
$d = array();$kb=array('a','b','c','d');$out = $a;
foreach($kb as $k){
    if(!empty(${$k})) $out = array_intersect($out,${$k});
};
print_r($out);
// The result is array

// The result is empty array

print_r(array_intersect($a,$b,$c,$d));?>

If you want to use this function with arrays which have sometimes the same value several times, it won't be checked if they're existing in the second array as much as in the first.
So I delete the value in the second array, if it's found there:

<?php
$firstarray = array(1, 1, 2, 3, 4, 1);
$secondarray = array(4, 1, 6, 5, 4, 1);//array_intersect($firstarray, $secondarray): 1, 1, 1, 4foreach ($firstarray as $key=>$value){
    if (!in_array($value,$secondarray)){
        unset($firstarray[$key]);
    }else{
        unset($secondarray[array_search($value,$secondarray)]);
    }
}//$firstarray: 1, 1, 4?>

<?phpfunction key_values_intersect($values,$keys) {
   foreach($keys AS $key) {
      $key_val_int[$key] = $values[$key];
      }
   return $key_val_int;
   }$big = array("first"=>2,"second"=>7,"third"=>3,"fourth"=>5);
$subset = array("first","third");print_r(key_values_intersect($big,$subset));?>

This will return:

Array ( [first] => 2 [third] => 3 )

<?php

    $valid_ids = array ('user_id', 'item_id', 'order_id');

    if ($id = current (array_intersect ($valid_ids, array_keys ($_GET))))

    {

        // do some stuff with it

    }

    else

        // error - invalid id passed, or none at all

?>



...which could be useful for constructing an SQL query, or some other situation where testing for them one by one might be too clumsy.

foreach ($firstarray as $key=>$value){
    if (!in_array($value,$secondarray)){
        unset($firstarray[$key]);
    }
}

This leaves $firstarray as the intersection.

Seems to work fine & reasonably quickly.

<?

$vals = array("Blue","Green","Pink","Yellow");
$db_field = "0,2,3";

echo implode(", ", array_flip(array_intersect(array_flip($vals), explode(",", $db_field))));

// will output "Blue, Pink, Yellow"

?>

<?php

function array_intersect_recursive($array1, $array2)

{

  foreach($array1 as $key => $value)

  {

    if (!isset($array2[$key]))

    {

      unset($array1[$key]);

    }

    else

    {

      if (is_array($array1[$key]))

      {

        $array1[$key] = array_intersect_recursive($array1[$key], $array2[$key]);

      }

      elseif ($array2[$key] !== $value)

      {

        unset($array1[$key]);

      }

    }

  }

  return $array1;

}

?>

<?php
if(array_unique($b + $a) === $b)
//...
?>

Actually, PHP ought to have a function that does this for you. But the above example works.

If array_intersect() doesn't appear to be working, check your inputs using var_dump() to make sure you're not trying to intersect an array of integers with an array of strings.

<?php

function matched_main_numbers($string, $string2)

{

$string = "04 16 17 20 29";

$arr1 = explode(" ", $string);
$string2 = "45 34 04 29 16";

$arr2 = explode(" ", $string2);
$array = array_intersect($arr1, $arr2);

$comma_separated = implode($array);
$str = $comma_separated;
$balls = "$comma_separated";

$matched_balls = chunk_split($balls,2," ");

$matched_balls =" $matched_balls";
$number_of_matched_main_balls = strlen($str);

$number_of_matched_main_balls = ($number_of_matched_main_balls/2);

$numbers = "You matched $number_of_matched_main_balls main balls";

return

$numbers;

       
}

?>

<?php
function array_values_to_keys_r($array, $fill_value = null)
{
    $flipped = [];
    foreach ($array as $key => $value) {
        if (is_array($value)) {
            $flipped [$key] = array_values_to_keys_r($value);
        } else {
            $flipped [$value] = $fill_value;
        }
    }
    return $flipped;
}
?>

<?php

$one

= range(1, 250000);
$two = range(50000, 150000);$start = microtime(true);$intersection = array_intersect($one, $two);

echo

"Did it in ".( microtime(true) - $start )." seconds.n";$start = microtime(true);$intersection = array_flip(array_intersect_key(array_flip($one), array_flip($two)));

echo

"Did it in ".( microtime(true) - $start )." seconds.n";?>

Did it in 0.89163708686829 seconds.
Did it in 0.038213968276978 seconds.

<?php
/**
examines two arrays and returns the intersected arrays with matching keys (ignores duplicate keys)
*/
function simple_array_intersect($a,$b) {
    $a_assoc = $a != array_values($a);
    $b_assoc = $b != array_values($b);
    $ak = $a_assoc ? array_keys($a) : $a;
    $bk = $b_assoc ? array_keys($b) : $b;
    $out = array();
    for ($i=0;$i<sizeof($ak);$i++) {
        if (in_array($ak[$i],$bk)) {
            if ($a_assoc) {
                $out[$ak[$i]] = $a[$ak[$i]];
            } else {
                $out[] = $ak[$i];
            }
        }
    }
    return $out;
}?>

You can try this out with this:

<?php
// create a large array (simple)
$first = array();
for ($i=500;$i<500000;$i++) {
    $first[] = $i;
}
// create a smaller array (associative)
$second = array();
for ($i=499990;$i<500000;$i++) {
    $second[$i] = rand();
}
echo microtime(true)."n";
// built-in function
print_r(array_intersect($first,$second));
echo microtime(true)."n";
// favour simple array as match
print_r(simple_array_intersect($first,$second));
echo microtime(true)."n";
// favour associative keys for match
print_r(simple_array_intersect($second,$first));
echo microtime(true)."n";?>

For example: array( array( 'red' ), array( 'white', 'blue' ) ) represents "red OR ( white AND blue )".  array( 'red', array( 'white', 'blue' ) ) would work, too, BTW.

If I have array( 'red' ) and I want to see if it matches the AND/OR array, I use the following function.  It returns the matched array,

but can just return a boolean if that's all you need:

<?php

$needle = array( array( 'red' ), array( 'white', 'blue' ) );

$haystack = array( 'red' );

function

findMatchingArray( $needle, $haystack ) {

    foreach( $needle as $element ) {

        $test_element = (array) $element;

        if( count( $test_element ) == count( array_intersect( $test_element, $haystack ) ) ) {

            return $element;

        }

    }

    return

false;

}

?>



Pretty tough to describe what I needed it to do, but it worked.  I don't know if anyone else out there needs something like this, but hope this helps.

<?php

function my_array_intersect($a,$b)

{

        for($i=0;$i<sizeof($a);$i++)

        {

                $m[]=$a[$i];

        }

        for($i=0;$i<sizeof($a);$i++)

        {

                $m[]=$b[$i];

        }

        sort($m);

        $get=array();

        for($i=0;$i<sizeof($m);$i++)

        {

                if($m[$i]==$m[$i+1])

                $get[]=$m[$i];

        }

        return $get;

}

?>



Barış ÇUHADAR

189780@gmail.com

array_intersect([false], [0]) == [];

Even in PHP 7.1