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I found this in tutorial on how to import excel in PHP but I cant find it in internet whats the use of & in the function parameter?

Here is the code: 

<?php
    $data = array(
        array("First Name" => "Nitya", "Last Name" => "Maity", "Email" => "nityamaity87@gmail.com", "Message" => "Test message by Nitya"),
    );

    function filterData(&$str) <--------------THIS LINE--------<
    {
        $str = preg_replace("/\t/", "\\t", $str);
        $str = preg_replace("/\r?\n/", "\\n", $str);
        if(strstr($str, '"')) $str = '"' . str_replace('"', '""', $str) . '"';
    }

    // file name for download
    $fileName = "codexworld_export_data" . date('Ymd') . ".xls";

    // headers for download
    header("Content-Disposition: attachment; filename=\"$fileName\"");
    header("Content-Type: application/vnd.ms-excel");

    $flag = false;
    foreach($data as $row) {
        if(!$flag) {
            // display column names as first row
            echo implode("\t", array_keys($row)) . "\n";
            $flag = true;
        }
        // filter data
        array_walk($row, 'filterData');
        echo implode("\t", array_values($row)) . "\n";
    }

    exit;
?>

edited

Does this line the same as function filterData($params) ?

user3678528
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Pure Rhymer Organization
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1 Answers1

1

With that "&" you are passing the variable by reference and not by value

http://php.net/manual/en/language.references.pass.php

No it is not the same

<?php

function filterData(&$str) 
{
    $str .= "new";
}
$a = "Hello";
filterData($a);
echo $a;
?>

In this case the system prints Hellonew

When you use the "&" every change you make to the variable still valid even outside the function. But please have a look on the link because my explanation is short and not complete (should be good for you to understand the difference between reference and value even for performance e security problems)

Davide
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