How can print a json response with php

Question

I'm building a simil web-service in php. This web service can read all record from a table of database and return a list of it in json format.

This is the code of my getArticoli.php file:

<?php
require_once('lib/connection.php');
$query_Articolo = "SELECT CodArticolo,NomeArticolo,Quantita,CodiceBarre, PrezzoAttuale, PrezzoRivenditore,PrezzoIngrosso 
         FROM VistaArticoli ";

$result_Articoli = $connectiondb->query($query_Articolo);
$answer          = array ();
while ($row_Articoli = $result_Articoli->fetch_assoc()) {
    $answer[] = ["id"                => $row_Articoli['CodArticolo'],
                 "nome"              => '"' . $row_Articoli['NomeArticolo'] . '"',
                 "quantita"          => $row_Articoli['Quantita'],
                 "codiceBarre"       => $row_Articoli['CodiceBarre'],
                 "codartFornitore"   => $row_Articoli['CodiceBarre'],
                 "PrezzoAttuale"     => $row_Articoli['PrezzoAttuale'],
                 "prezzoRivenditore" => $row_Articoli['prezzoRivenditore'],
                 "prezzoIngrosso"    => $row_Articoli['prezzoIngrosso']];
}
//echo "fine";
echo json_encode($answer);
?>

Now, if I try to open this page, with this url: http://localhost/easyOrdine/getArticoli.php

I don't get the json_response.

In the table of database, there are 1200 records. If I try to insert an echo message in while cycle, I see it.

I have noticed that the problem lays with this field:

"nome"=>'"'.$row_Articoli['NomeArticolo'].'"'

If I remove this field from the response, I can correctly see the json response.

In this field there are any character from a-z/0-9 and special character like "/ * ? - and other".

It is possible that these special character can cause any error of the json answer?

EDIT I have limit at 5 my query and this is the response:

 [{"id":"878","0":"ACCESSORIO PULIZIA PUNTE DISSALDANTE 3 MISURE","quantita":"1","codiceBarre":"DN-705100","codartFornitore":"DN-705100","PrezzoAttuale":"14.39","prezzoRivenditore":null,"prezzoIngrosso":null},
{"id":"318","0":"ACCOPPIANTORE RJ11 TELEFONICO VALUELINE VLTP90920W","quantita":"20","codiceBarre":"5412810196043","codartFornitore":"5412810196043","PrezzoAttuale":"0.68","prezzoRivenditore":null,"prezzoIngrosso":null},
{"id":"320","0":"ACCOPPIATORE AUDIO RCA VALUELINE VLAB24950B","quantita":"5","codiceBarre":"5412810214136","codartFornitore":"5412810214136","PrezzoAttuale":"1.29","prezzoRivenditore":null,"prezzoIngrosso":null},
{"id":"310","0":"ACCOPPIATORE RJ45 VALUELINE VLCP89005W","quantita":"8","codiceBarre":"5412810228843","codartFornitore":"5412810228843","PrezzoAttuale":"0.38","prezzoRivenditore":null,"prezzoIngrosso":null},
{"id":"311","0":"ACCOPPIATORE USB2 VALUELINE VLCP60900B","quantita":"5","codiceBarre":"5412810179596","codartFornitore":"5412810179596","PrezzoAttuale":"1.80","prezzoRivenditore":null,"prezzoIngrosso":null}]

Why can't you use just `"nome"=> $row_Articoli['NomeArticolo']` and leave json parser escaping? — marian0, Jan 17 '17 at 13:55
You are on the right way, but I think the main problem is this '"'. and this .'"' in '"'.$row_Articoli['NomeArticolo'].'"' — Oliver, Jan 17 '17 at 13:56
Have you tried enabling error reporting ? That might help you figure out why the JSON can't be constructed. — roberto06, Jan 17 '17 at 13:59
@marian0, at first time, I have write "nome"=>$row_Articoli['NomeArticolo'] after I'm try to change this code to fixed my problem. But not working — bircastri, Jan 17 '17 at 14:10
limit your select to a few lines (say, 5) do a `var_dump` for `$answer`. (And post it in your question). — yivi, Jan 17 '17 at 14:14
@bircastri add `ini_set('display_errors', 'on');` and `error_reporting(E_ALL | E_STRICT);` at the beginning of your file. — roberto06, Jan 17 '17 at 14:14
if it's a `json_encode` problem, error reporting will say nothing. `json_encode` returns `false` but do not trigger an error. — yivi, Jan 17 '17 at 14:15
I'm try to insert your code but I don't have any message. @yivi I think that your comment it is ok, the problem is the json_encode procedure, but I'm not able to fixed it — bircastri, Jan 17 '17 at 14:17
What code did you try to insert? update your question with your attempt, please, is not clear otherwise. — yivi, Jan 17 '17 at 14:18
Something is wrong there. The second field (article name) has a "0" key. You are making more changes in code that the ones you reflect in your answer. And you didn't make the `var_dump`. — yivi, Jan 17 '17 at 14:22

yivi · Accepted Answer · 2017-01-17T14:40:01.310

First, remove those extraneous quote characters. You don't need them and they could hurt you down the road:

while ($row_Articoli = $result_Articoli->fetch_assoc()) {
    $answer[] = [
                 "id"                => $row_Articoli['CodArticolo'],
                 "nome"              => $row_Articoli['NomeArticolo'],
                 "quantita"          => $row_Articoli['Quantita'],
                 "codiceBarre"       => $row_Articoli['CodiceBarre'],
                 "codartFornitore"   => $row_Articoli['CodiceBarre'],
                 "PrezzoAttuale"     => $row_Articoli['PrezzoAttuale'],
                 "prezzoRivenditore" => $row_Articoli['prezzoRivenditore'],
                 "prezzoIngrosso"    => $row_Articoli['prezzoIngrosso']
               ];
}

Then, run your query as is (without the LIMIT), and afterwards run echo json_last_error_msg()';, which could give you a hint to what's going on.

Also, being that your DB is in italian, maybe its encoding is not UTF-8. json_encode requires UTF-8 encoded data. So you may try to utf8_encode your article names before json_encoding the array:

             "nome"              => utf8_encode($row_Articoli['NomeArticolo']),

And see what you get.

Changing your DB charset to 'utf8mb4' could do the trick as well, and it is usually recommended.

thanks you. Your code works. Now for my database, this charset is reccomended to the italian ??? thanks — bircastri, Jan 17 '17 at 14:36
Set it to `utf8mb4`. Check this out: http://stackoverflow.com/questions/279170/utf-8-all-the-way-through — yivi, Jan 17 '17 at 14:38

How can print a json response with php

1 Answers1