Multiple keyword loop?

If I have this text file:

---keywords.txt
banana
grapes
apple
mango
orange
pear
coconut
strawberry
---

..and I want to see if any of those words are in a string:

ie:

If (banana or apple or orange or pear are contained in my text file) {
$keyword = "the word that was found";
}

for example: if apple was a line in the text file, then:

$keyword = "apple"; //apple was found in the list and has become the $keyword

also, if there are multiple keywords - just the first one found would do.

ie: If both apple and pear were in the list then Keyword would become apple.

I can find examples of how to check if a word is in a list online, but I can't find an example of how to check if a word is in a list and then make that word the value of a variable.

 

From the docs of: http://www.php.net//manual/en/function.fgets.php + the isset check:

<?php
// Items or item to look for
$lookingFor = array(
    'orange' => true,
    'apple' => true,
);
$keywordFound = false;
// Open file
$handle = fopen("keywords.txt", "r");
if ($handle) {
     // Get line
     while (($buffer = fgets($handle, 4096)) !== false) {
        // If line is found in array, output and stop looking
        if (isset($lookingFor[$buffer])) {
             $keywordFound  = $buffer;
             break;
        }
    }
    if (!feof($handle)) {
        echo "Error: unexpected fgets() fail\n";
    }
    fclose($handle);
}

if ($keywordFound  !== false) {
    echo   echo "$keywordFound found in file";
}

PHP:

 

Thank you - that is just what I need!

I appreciate your response