CODEWITHSUNDEEP
phpfunctionreturn
NicolaPez
NicolaPez

Reputation: 587

PHP function return don't work

i have a problem. I write this function tu recover a previous branch from my DB entity, and i want that the function return a string with I can see this information. this is the code:

function stampaOggettoCollezione($tipoOggetto, $id, $connection, $percorso="")
{
    $i=0;

    switch($tipoOggetto)
    {
        case 'casaeditrice':
            return $percorso;
            break;

        case 'storia':
            $dati = array("storia", "IDCasaEditrice", "casaeditrice");
            break;

        case 'testata':
            $dati = array("testata", "IDStoria", "storia");
            break;

        case 'albo':
            $dati = array("albo", "IDTestata", "testata");
            break;
    }

            $sql = "SELECT * FROM ".$dati[0]." WHERE ID=$id";
            $result=mysqli_query($connection,$sql);
            $IDSuperiore=mysqli_fetch_array($result)[$dati[1]];

            $sql = "SELECT * FROM ".$dati[2]." WHERE ID=$IDSuperiore";
            $result = mysqli_query($connection, $sql);
            $nomeSuperiore=mysqli_fetch_array($result)['nome'];

            $percorso = $percorso . $nomeSuperiore;

            stampaOggettoCollezione($dati[2], $IDSuperiore, $connection, $percorso);
}

i'm sure that code works, i try some echo in the code to check the final path. My problem is that i can't write the return like a string in my webpage. What do you think about? there's some problem with the declaration? Thanks

Upvotes: 2

Views: 112

Answers (2)

user5051310
user5051310

Reputation:

Replace

stampaOggettoCollezione($dati[2], $IDSuperiore, $connection, $percorso);

with

return stampaOggettoCollezione($dati[2], $IDSuperiore, $connection, $percorso);

You have to pass $percorso all the way back out of all the calls to stampaOggettoCollezione and back to the original call. Read more about recursion on the Internets.

Alternatively, I believe you could achieve the same effect if you change your function to build a query that joins on tables. It will remove the need for recursion, reduce the number of database calls, and should work without changing anything but the function itself.

// dynamically queries more tables based on what the inital table to query is
function stampaOggettoCollezione($tipoOggetto, $id, $connection, $percorso="")
{
    $selectQuery = "SELECT ";
    $columnsToSelect = "";
    $fromQuery = "";
    $whereClause = " WHERE ";

    switch($tipoOggetto) {
        case 'albo':
            $columnsToSelect .= ", a.nome AS aNome";
            $fromQuery = " LEFT JOIN albo a ON t.ID = a.IDTestata";
        case 'testata':
            $columnsToSelect .= ", t.nome AS tNome";
            $fromQuery = " LEFT JOIN testata t ON s.ID = t.IDStoria" . $fromQuery;
        case 'storia':
            $columnsToSelect .= ", s.nome AS sNome";
            $fromQuery = " LEFT JOIN storia s ON ce.ID = s.IDCasaEditrice" . $fromQuery;
        case 'casaeditrice':
            $columnsToSelect .= ", ce.nome AS ceNome";
            $fromQuery = " FROM casaeditrice ce" . $fromQuery;
            break;
    }
    // remove the first `, `
    $selectQuery .= substr($columnsToSelect, 2);

    switch($tipoOggetto)
    {
        case 'casaeditrice':
            $whereClause .= "c.ID = $id";
            break;
        case 'storia':
            $whereClause .= "s.ID = $id";
            break;
        case 'testata':
            $whereClause .= "t.ID = $id";
            break;
        case 'albo':
            $whereClause .= "a.ID = $id";
            break;
    }

    $qry = $selectQuery . $fromQuery . $whereClause;

    $result=mysqli_query($connection,$sql);
    $nomeSuperiore= "";
    $nomes = mysqli_fetch_array($result);
    // might take some work to get the output in the right order
    foreach($nomes as $nome)
        $nomeSuperiore .= $nome;

    return $nomeSuperiore;
}

Upvotes: 1

George
George

Reputation: 2422

I'm not sure I understand because the english is difficult to understand, but it seems that all you need to do is write:

return $result;

at the end of the function, or whichever string variable you want to return. Then use echo stampaOggettoCollezione(arguments...) after the function to have this value echoed.

Upvotes: 1

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