Question

I have a private message system and I have this function that returns the IDs of all the users in the conversation (except the sender):

function findOtherUsersInConversation($conversation_id) {
    $sender = findMessageSenderId($conversation_id);
    $query  = mysql_query("SELECT user_id FROM message_partecipant WHERE conversation_id =   '$conversation_id' AND user_id !=$sender");
    while ($row = mysql_fetch_array($query)) {
        $user_id = $row['user_id'];
        print_r($user_id);
    }
}

print_r return the Ids (for instance id100 and id 101)like this:

100101//which is not what i'm trying to do

I have another function that find the username in the database so for each user id I would like to get their usernames in this format:

echo usernameFromId($user_id)// this should echo out all the username like this (user a, user b, user c)

I think I have to do a foreach loop but I can’t think how.

Answer 1

Try this:

function findOtherUsersInConversation($conversation_id){
    $sender = findMessageSenderId($conversation_id);
    $query =  mysql_query("SELECT user_id FROM message_partecipant WHERE conversation_id =   '$conversation_id' AND user_id !=$sender");
    $users = array();
    while ($row = mysql_fetch_array($query)) {
        $users[] = usernameFromId($row['user_id']); // fetch user name and add it to array
    }
    return implode(', ', $users); // return a string separated by commas
}

findOtherUsersInConversation(10); // conversation id 10