php改json数据格式的问题

Question

 
<?php
header("Content-Type: text/html; charset=UTF-8");
$con = mysql_connect("localhost","root","root");
if (!$con)//判断是否连接成功
{
die('Could not connect: ' . mysql_error());
}
mysql_set_charset('utf8',$con);//指定连接数据库的编码
mysql_select_db("emp");
  
$q=mysql_query("SELECT * FROM tianqi ");//取出tianqi中所有的数据   while($en=mysql_fetch_object($q)) echo json_encode($en,JSON_UNESCAPED_UNICODE);//打印结果     exit;
mysql_close();  
大家看下我这个代码  我发出去的值是这样的{"id":"1","location":"汉字","oxygen":"3.33","negative":"23.2","humidity":"22","temp":"2.33","pm":"6"}{"id":"4","location":"百度","oxygen":"13","negative":"151","humidity":"1","temp":"1","pm":"1151"}
 但是我想把发出去的这段代码改成这样：[{"id":"1","location":"汉字","oxygen":"3.33","negative":"23.2","humidity":"22","temp":"2.33","pm":"6"}{"id":"4","location":"百度","oxygen":"13","negative":"151","humidity":"1","temp":"1","pm":"1151"}]
也就是给这段代码加一个中括号，请问下怎么改。  
 

Answer 1

while($en=mysql_fetch_object($q))
 $en = array($en);
    echo json_encode($en,JSON_UNESCAPED_UNICODE);//打印结果 
 
    exit;

Answer 2

@qc963430178 错了返回的值是false

Answer 3

  while($en=mysql_fetch_object($q))
   
echo json_encode(array($en),JSON_UNESCAPED_UNICODE);//打印结果     exit;我改了这个，结果是这样[{"id":"1","location":"汉字","oxygen":"3.33","negative":"23.2","humidity":"22","temp":"2.33","pm":"6"}][{"id":"4","location":"百度","oxygen":"13","negative":"151","humidity":"1","temp":"1","pm":"1151"}]

Answer 4

$arr = array();
while($en=mysql_fetch_object($q))
     $arr[] = $en;
echo json_encode($arr,JSON_UNESCAPED_UNICODE);//打印结果 
exit;