Parsing JSON object in PHP using json_decode - php

Question

I tried to request the weather from a web service supplying data in JSON format. My PHP request code, which did not succeed was:
$url="http://www.worldweatheronline.com/feed/weather.ashx?q=schruns,austria&format=json&num_of_days=5&key=8f2d1ea151085304102710";
$json = file_get_contents($url);
$data = json_decode($json, TRUE);
echo $data[0]->weather->weatherIconUrl[0]->value;
This is some of the data that was returned. Some of the details have been truncated for brevity, but object integrity is retained:
{ "data":
{ "current_condition":
[ { "cloudcover": "31",
... } ],
"request":
[ { "query": "Schruns, Austria",
"type": "City" } ],
"weather":
[ { "date": "2010-10-27",
"precipMM": "0.0",
"tempMaxC": "3",
"tempMaxF": "38",
"tempMinC": "-13",
"tempMinF": "9",
"weatherCode": "113",
"weatherDesc": [ {"value": "Sunny" } ],
"weatherIconUrl": [ {"value": "http:\/\/www.worldweatheronline.com\/images\/wsymbols01_png_64\/wsymbol_0001_sunny.png" } ],
"winddir16Point": "N",
"winddirDegree": "356",
"winddirection": "N",
"windspeedKmph": "5",
"windspeedMiles": "3" },
{ "date": "2010-10-28",
... },
... ]
}
}
}

Answer 1

This appears to work:
$url = 'http://www.worldweatheronline.com/feed/weather.ashx?q=schruns,austria&format=json&num_of_days=5&key=8f2d1ea151085304102710%22';
$content = file_get_contents($url);
$json = json_decode($content, true);
foreach($json['data']['weather'] as $item) {
print $item['date'];
print ' - ';
print $item['weatherDesc'][0]['value'];
print ' - ';
print '<img src="' . $item['weatherIconUrl'][0]['value'] . '" border="0" alt="" />';
print '<br>';
}
If you set the second parameter of json_decode to true, you get an array, so you cant use the -> syntax. I would also suggest you install the JSONview Firefox extension, so you can view generated json documents in a nice formatted tree view similiar to how Firefox displays XML structures. This makes things a lot easier.

Answer 2

If you use the following instead:
$json = file_get_contents($url);
$data = json_decode($json, TRUE);
The TRUE returns an array instead of an object.

Answer 3

Try this example
$json = '{"foo-bar": 12345}';
$obj = json_decode($json);
print $obj->{'foo-bar'}; // 12345
http://php.net/manual/en/function.json-decode.php
NB - two negatives makes a positive . :)

Answer 4

Seems like you forgot the ["value"] or ->value:
echo $data[0]->weather->weatherIconUrl[0]->value;

Answer 5

When you json decode , force it to return an array instead of object.
$data = json_decode($json, TRUE); -> // TRUE
This will return an array and you can access the values by giving the keys.

Answer 6

You have to make sure first that your server allow remote connection so that the function file_get_contents($url) works fine , most server disable this feature for security reason.

Answer 7

While editing the code (because mild OCD), I noticed that weather is also a list. You should probably consider something like
echo $data[0]->weather[0]->weatherIconUrl[0]->value;
to make sure you are using the weatherIconUrl for the correct date instance.