致命错误：找不到“Services_JSON”类

I try to create a very simple web application on 000webhosting, but when I try to implement this:

<?php

include_once("JSON.php");
$json = new Services_JSON();

$link = mysql_pconnect("******", "******", "******") or die("Could not connect");
mysql_select_db("******") or die("Could not select database");

$arr = array();

$rs = mysql_query("SELECT * FROM users");
while($obj = mysql_fetch_object($rs)) {
    $arr[] = $obj;
}

Echo $json->encode($arr);

?>

But I got this warning/error. Could you help me please?

Warning: include_once(JSON.php) [function.include-once]: failed to open stream: No such file or directory in /home/a1622045/public_html/index.php on line 3

Warning: include_once() [function.include]: Failed opening 'JSON.php' for inclusion (include_path='.:/usr/lib/php:/usr/local/lib/php') in /home/a1622045/public_html/index.php on line 3

Fatal error: Class 'Services_JSON' not found in /home/a1622045/public_html/index.php on line 4

Change this:

Echo $json->encode($arr);

to this:

echo json_encode($arr);

and remove this:

include_once("JSON.php");
$json = new Services_JSON();

The program you are working on uses an old PEAR library, which converts JSON object notation into PHP arrays, and vice versa. However PHP has had the ability to do this natively for many years, and so your code is relying on a dependency it does not need.

I have switched Echo to echo too - PHP keywords may work in mixed-case format, but it is a good convention to write them in lower-case, as per the manual.

As @Krish-r said, Services_JSON is PEAR package provides a simple encoder and decoder for JSON notation.

  1. failed to open stream : verify the JSON.php is readable and in the same dire than your script
  2. 'Services_JSON' not found : if it's not already installed, install Services_JSON from pear lib ( https://pear.php.net/package/Services_JSON ) instead load "JSON.php" wo look do the same thing .

To do this use [1] :

pear install Services_JSON

Now no need to include_once("JSON.php").

[1] https://pear.php.net/manual/en/guide.users.commandline.installing.php