Json encode an entire mysql result set

I want to get json with php encode function like the following

<?php 
  require "../classes/database.php";

  $database = new database();
  header("content-type: application/json");
  $result = $database->get_by_name($_POST['q']);   //$_POST['searchValue']

  echo '{"results":[';
  if($result)
  {
     $i = 1;
     while($row = mysql_fetch_array($result))
     {
        if(count($row) > 1) 
        {
           echo json_encode(array('id'=>$i, 'name' => $row['name']));
           echo ",";
        }
        else 
        {
           echo json_encode(array('id'=>$i, 'name' => $row['name']));
        }
        $i++; 
     }
  }
  else
  {
     $value = "FALSE";
     echo json_encode(array('id'=>1, 'name' => ""));  // output the json code
  }

  echo "]}";

i want the output json to be something like that

{"results":[{"id":1,"name":"name1"},{"id":2,"name":"name2"}]}

but the output json is look like the following

{"results":[{"id":1,"name":"name1"},{"id":2,"name":"name2"},]}

As you realize that there is comma at the end, i want to remove it开发者_如何学Python so it can be right json syntax, if i removed the echo ","; when there's more than one result the json will generate like this {"results":[{"id":1,"name":"name1"}{"id":2,"name":"name2"}]} and that syntax is wrong too

Hope that everybody got what i mean here, any ideas would be appreciated

If I were you, I would not json_encode each individual array, but merge the arrays together and then json_encode the merged array at the end. Below is an example using 5.4's short array syntax:

$out = [];
while(...) {
  $out[] = [ 'id' => $i, 'name' => $row['name'] ];
}
echo json_encode($out);

Do the json_encoding as the LAST step. Build your data structure purely in PHP, then encode that structure at the end. Doing intermediate encodings means you're basically building your own json string, which is always going to be tricky and most likely "broken".

$data = array();
while ($row = mysql_fetch_array($result)) {
   $data[] = array('id'=>$i, 'name' => $row['name']);
}
echo json_encode($data);

build it all into an array first, then encode the whole thing in one go:

$outputdata = array();
while($row = mysql_fetch_array($result)) {
    $outputdata[] = $row;
}

echo json_encode($outputdata);