Get specific data from json using php - php

Question

This is json data i received:
{"id":"8","cardnum":"5678887","point_collected":"26","date":"2015-05-06"}
{"id":"15","cardnum":"3435435","point_collected":"20","date":"2015-05-04"}
{"id":"11","cardnum":"5678887","point_collected":"50","date":"2015-05-03"}
{"id":"12","cardnum":"5678887","point_collected":"80","date":"2015-05-02"}
{"id":"14","cardnum":"5678887","point_collected":"10","date":"2015-05-02"}
I want to get the "cardnum" for comparison with my $usercard, and display all the result with the same "cardnum" and encode into json again.
This is my current code:
$decodeTrans=json_decode($transJson, true);
$response = array();
$usercard = "5678887";
foreach ($decodeTrans as $dt)
{
$membercard = $dt['cardnum'];
if ($membercard == $usercard)
{
$response["success"] = 1;
$response ['id'] = $dt['id'];
$response ['card_number'] = $membercard;
$response ['point_collected'] = $dt['point'];
$response ['date'] = $dt['date'];
echo json_encode($response);
}
}
}
}
I get this error: Invalid argument supplied for foreach()
Anyone can help? Thanks in advance.

Answer 1

Your input is not a valid JSON string. However, each line is still a valid JSON string. Update your code to split the $transJson and convert each line to PHP object using json_decode:
$response = array();
$usercard = "5678887";
foreach(explode("\n", $transJson) as $line)
{
$dt = json_decode(trim($line), true);
$membercard = $dt['cardnum'];
if ($membercard == $usercard)
{
$response["success"] = 1;
$response ['id'] = $dt['id'];
$response ['card_number'] = $membercard;
$response ['point_collected'] = $dt['point_collected'];
$response ['date'] = $dt['date'];
echo json_encode($response);
}
}
The demo: http://sandbox.onlinephpfunctions.com/code/3335a3fa9edb5a3b8d7e73fd85d4bad806e5ac92