PHP获取查询结果不起作用

Question

I am trying to run a PHP code to query a select statement in a mysql database and return values into text.

Here is my code:

<?php
function getFirstname($db) {
    $sql = "SELECT firstname FROM Users WHERE username = 'test'";
    foreach ($db->query($sql) as $row) {
        $row['firstname'] = $firstname;
    }
}
?>

and then i'm trying to echo it out.

<?php echo $firstname  ?>

Is there something i'm doing wrong?

The only error i get is...

Undefined variable: firstname in /home/test/public_html/test/index.php on line 42

Answer 1

Your function needs to return the value in order that you can use the value later.

function getFirstname($db) {
    $firstname=false;
    $sql = "SELECT `firstname` FROM `Users` WHERE `username` = 'test';";
    foreach ($db->query($sql) as $row) {
        $firstname=$row['firstname'];
    }
    return $firstname;
}

$firstname=getFirstname( $db );
echo $firstname;



function getUserdata($db) {
    $data=array();
    $sql = "SELECT `firstname` FROM `Users` WHERE `username` = 'test';";
    foreach( $db->query($sql) as $row ) {
        $data['firstname']=$row['firstname'];
        $data['lastname']=$row['lastname'];
    }
    return $data;
}

$data=getUserdata($db);
echo $data['firstname'].' '.$data['lastname'];