Decoding and looping through PHP JSON array - php

Question

I have the following deocoded JSON array.
I need to access the "type" inside the context, as well as I need to loop through each of the values in the payload. How do I do that?
{
"RequestHeader":
{
"mess": "am putting it on my wall....",
"created_time": "2010-08-24T09:01:25+0000"
},
"context" :
{
"type": "friends,circles"
}
"payload" [ {12345},{12345} ,{2345} ]
}
I tried the following, but it doesn't work
$decoded = json_decode($json_string);
for ($i=0;$i<payload.length;++$i)
{
$id=$decoded->payload[$i];
//do some operation with the id
}

Answer 1

First of all the JSON you provided is invalid. Supposedly the valid one should look like this
{
"RequestHeader": {
"mess": "am putting it on my wall....",
"created_time": "2010-08-24T09:01:25+0000"
},
"context": {
"type": "friends,circles"
},
"payload": [
12345,
12345,
2345
]
}
After you've fixed the problem with JSON provider it will be quite easy to access data
<?php
$json = <<<'JSON'
{
"RequestHeader": {
"mess": "am putting it on my wall....",
"created_time": "2010-08-24T09:01:25+0000"
},
"context": {
"type": "friends,circles"
},
"payload": [
12345,
12345,
2345
]
}
JSON;
$data = json_decode($json, true);
$type = $data['context']['type'];
var_dump($type);
foreach($data['payload'] as $id) {
var_dump($id);
}
Remember to make sure you check that the data actually exists before accessing it, e.g. isset($data['context']['type']) unless you are absolutely sure in it's integrity.

Answer 2

When you use json_decode method, the output will be nested arrays
So for example to access context type you need to do the following
echo $decoded["context"]["type"];
And to loop on payload you need to do the following
for ($i=0;$i<$decoded["payload"].length;++$i)
{
$id=$decoded["payload"][$i];
//do some operation with the id
}