Extracting values from JSON data - php

Question

I have the JSON data given below. The 'crop' array contains multiple array of crop price, I want to get average crop price of all districts(using 'district_id').
<i>{
"status": "ok",
"count": 7,
"crop": [
{
"id": "133",
"crop_id": "81",
"price": "45.00",
"description": null,
"user_id": "27",
"block_id": "1",
"longitude": "87.8661808",
"latitude": "23.2340073",
"date": "2014-02-03",
"time": "12:44:43",
"district_id": "1"
},
{
"id": "135",
"crop_id": "81",
"price": "10.50",
"description": null,
"user_id": "27",
"block_id": "1",
"longitude": "87.8662402",
"latitude": "23.2339822",
"date": "2014-02-03",
"time": "12:44:54",
"district_id": "1"
},
{
"id": "143",
"crop_id": "81",
"price": "35",
"description": null,
"user_id": "27",
"block_id": "1",
"longitude": "0.0",
"latitude": "0.0",
"date": "2014-02-03",
"time": "13:12:50",
"district_id": "1"
},
{
"id": "146",
"crop_id": "81",
"price": "85",
"description": null,
"user_id": "27",
"block_id": "1",
"longitude": "0.0",
"latitude": "0.0",
"date": "2014-02-03",
"time": "14:29:07",
"district_id": "1"
},
{
"id": "148",
"crop_id": "81",
"price": "25",
"description": null,
"user_id": "27",
"block_id": "1",
"longitude": "0.0",
"latitude": "0.0",
"date": "2014-02-03",
"time": "14:58:01",
"district_id": "1"
},
{
"id": "132",
"crop_id": "81",
"price": "10",
"description": null,
"user_id": "119",
"block_id": "34",
"longitude": "0.0",
"latitude": "0.0",
"date": "2014-02-03",
"time": "12:41:49",
"district_id": "4"
},
{
"id": "134",
"crop_id": "81",
"price": "12",
"description": null,
"user_id": "119",
"block_id": "34",
"longitude": "0.0",
"latitude": "0.0",
"date": "2014-02-03",
"time": "12:43:50",
"district_id": "4"
}
]
}</i>

Answer 1

Use json_decode method to convert it to an std_class or use the 2nd parameter of this method to convert it to an associated array.
Take a look at http://in1.php.net/json_decode
Once you decode it, you can easily access the variables like accessing properties of a class or as an array object if you are converting to an associated array

Answer 2

First you have too decode the JSON using json_decode function, then access using variables.

Answer 3

Do like this..
//Assign your JSON data to this $json variable as shown in the demo.
$arr = json_decode($json,1);
foreach($arr['crop'] as $arr1)
{
foreach($arr1 as $k=>$v)
{
if($arr1['district_id']==1)
{
$avgpr[] = $arr1['price'];
}
}
}
echo $avgprice = array_sum($avgpr)/count($avgpr);
OUTPUT :
40.1
Demo