PHP - JSON Data Parsing [duplicate] - php

Question

This question already has an answer here:
How to extract and access data from JSON with PHP?
(1 answer)
Closed 11 months ago.
All,
I have the following JSON Data. I need help writing a function in PHP which takes a categoryid and returns all URLs belonging to it in an array.
Something like this::
<?php
function returnCategoryURLs(catId)
{
//Parse the JSON data here..
return URLArray;
}
?>
{
"jsondata": [
{
"categoryid": [
20
],
"url": "www.google.com"
},
{
"categoryid": [
20
],
"url": "www.yahoo.com"
},
{
"categoryid": [
30
],
"url": "www.cnn.com"
},
{
"categoryid": [
30
],
"url": "www.time.com"
},
{
"categoryid": [
5,
6,
30
],
"url": "www.microsoft.com"
},
{
"categoryid": [
30
],
"url": "www.freshmeat.com"
}
]
}
Thanks

Answer 1

What about something like this :
You first use json_decode, which is php's built-in function to decode JSON data :
$json = '{
...
}';
$data = json_decode($json);
Here, you can seen what PHP kind of data (i.e. objects, arrays, ...) the decoding of the JSON string gave you, using, for example :
var_dump($data);
And, then, you loop over the data items, searching in each element's categoryid if the $catId you are searching for is in the list -- in_array helps doing that :
$catId = 30;
$urls = array();
foreach ($data->jsondata as $d) {
if (in_array($catId, $d->categoryid)) {
$urls[] = $d->url;
}
}
And, each time you find a match, add the url to an array...
Which means that, at the end of the loop, you have the list of URLs :
var_dump($urls);
Gives you, in this example :
array
0 => string 'www.cnn.com' (length=11)
1 => string 'www.time.com' (length=12)
2 => string 'www.microsoft.com' (length=17)
3 => string 'www.freshmeat.com' (length=17)
Up to you to build from this -- there shouldn't be much left to do ;-)

Answer 2

Try the built-in json_decode function.