Create json from array in PHP

Question

I have this little sql code:

try {
 $stmt = $conn->prepare("SELECT APPID FROM COMMENTROOM WHERE BADGEID=? GROUP BY APPID");
 $stmt->execute(array($badgeID));
 while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
 $row2[$i][0] = $row['APPID'];
 $i++;
 }
 } catch(PDOException $e) {
 echo 'ERROR: ' . $e->getMessage();
 $server_dir = $_SERVER['HTTP_HOST'] . rtrim(dirname($_SERVER['PHP_SELF']), '/\\');
 header('Location: http://' . $server_dir);
 exit();
 }

When I now print out the result with print(json_encode($row2)); I get the following:

[["0000000021"],["0000000037"],["0000000038"],["0000000039"],["0000000128"],["0000000130"]]

Since I already have this data I don't need to query the database. But I still need to forward it in the same format to my Java app. When I use

$output[] = json_encode($row2);
print(json_encode($output));

I get a different output:

["[[\"0000000021\"],[\"0000000037\"],[\"0000000038\"],[\"0000000039\"],[\"0000000128\"],[\"0000000130\"]]"]

I checked a few stackoverflow questions but I didn't find any that addresses the same problem.

Answer 1

You are json encoding it twice

$output[] = json_encode($row2);
print(json_encode($output));

Just do it once:

$output[] = $row2;
print(json_encode($output));

• erdomester: This adds another bracket to the result. So it begins with [[["0000000021" instead of [["0000000021"
• Steve: I dont understand what you are trying to do here at all - what was the purpose of creating the output array in the 1st place?
• erdomester: Actually I messed up the question. I have an array with 6 fields. These fields are populated from 3 SELECT FROM queries. Is there a way to transform this array into an output that normally result from an sql query? The output I need is like [{"APPNAME":"Enhanced Email","LINK":"http... I did this by creating a populating a temporary table then querying it but I think it's not the best way to do.
• Steve: @erdomester Please edit your question with your exact expected output so i can help you
• erdomester: I accepted this solution since you answered it. However the real answer is print(json_encode($row2;));.

Answer 2

EDIT Now I understand what you want...

$retval = array();
//as this while you can add as many items to the array as you want
while( $row = $stmt->fetch(PDO::FETCH_OBJ) ){
 $retval[] = $row;
}
echo json_encode( $retval );

Regards, hotzu

• erdomester: This changes the result. It now begins with {"data":[["0000000021", instead of [["0000000021",
• Zsolt Tolvaly: where do you want to use it? In a Javascript or a Java application?