如何使用for循环比较两个数组？

I have 2 explode arrays from the database. and this is what i did.

    $searches = explode(',', $searchengine);
    $icons = explode(',', $icon);
    $b = count($searches);
    $c = count($icons);

I also made an array to compare each explode array to.

$searchesa = array("google","yahoo","bing");
    $d = count($searchesa);
    $iconsa = array("facebook","twitter","googleplus","linkedin","pinterest","delicious","stumbleupon","diigo");
    $y = count($iconsa);

Then i used for loops to travel to different array indexes. But the result is wrong, and sometimes I have an error which says UNDEFINED OFFSET.

for ($a=0; $a <$d ; $a++) {
    if ($searches[$a] == $searchesa[$a]) 
            {echo '<br>'.$searchesa[$a].': check ';
        }else
        echo '<br>'.$searchesa[$a].': chok ';
    }

for ($x=0; $x <$y ; $x++) {
    if ($icons[$x] == $iconsa[$x]) 
        echo '<br>'.$iconsa[$x].': check ';
    else
        echo '<br>'.$iconsa[$x].': chok ';
}

If the index from the database and the array I made are the same, it will state check, else it will state chok.

I posted this in my comment, but I suppose the outline will work better in an answer.

I hope this could be of any help:

<?php
$array_a = ['test','test2']; // assume this is your first array
$array_b = ['test']; // assume this is the array you wan to compare against
$found = false;

foreach ($array_a as $key_a => $val_a) {
    $found = false;
    foreach ($array_b as $key_b => $val_b) {
       if ($val_a == $val_b) {
            echo '<br>'. $val_b .': check ';     
            $found = true;
        }     
    }
    if (!$found)
        echo '<br>'. $val_a .': chok ';
}
?>

EDIT: Please excuse me for not testing it.

This thing will loop through the first array, and compare it with every value in the other array.

Tip: You can easily put this in a function and call it like compare($arr1, $arr2)

$arraysAreEqual = ($a == $b); // TRUE if $a and $b have the same key/value pairs. 
$arraysAreEqual = ($a === $b); // TRUE if $a and $b have the same key/value pairs in the same order and of the same types.

taken via : PHP - Check if two arrays are equal

You can try in_array method:

$searchesa = array("google","yahoo","bing");
$iconsa = array("facebook","twitter","googleplus","linkedin","pinterest","delicious","stumbleupon","diigo",'google');

foreach($searchesa as $val){
    if(in_array($val, $iconsa)){
       echo "check";
    } else {
       echo "choke";
    }
}

Note: I've added "google" in $iconsa array.

If I understand you correctly this is what you are looking for:

// Lets prepare the arrays
$searchEngines = explode(',', $searchengine);
$icons = explode(',', $icon);

// Now let's define the arrays to match with
$searchEnginesCompare = array(
    'google',
    'yahoo',
    'bing'
);

$iconsCompare = array(
    'facebook',
    'twitter',
    'googleplus',
    'linkedin',
    'pinterest',
    'delicious',
    'stumbleupon',
    'diigo'
);

// Check the search engines
foreach ($searchEngines as $k => $searchEngine) {
    if (in_array($searchEngine, $searchEnginesCompare)) {
        echo $searchEngine." : check<br />";
    } else {
        echo $searchEngine." : failed<br />";
    }
}

// Now let's check the icons array
foreach ($icons as $k => $icon) {
    if (in_array($icon, $iconsCompare)) {
        echo $icon." : check<br />";
    } else {
        echo $icon." : failed<br />";
    }
}