Question

I’m trying to increase the readability of my code by creating additional functions but splitting get_current_weather_data() function causes the following error:

Fatal error: Call to a member function children() on a non-object in C:\xampp\htdocs\Twinz\src\weather.php on line 37

Line 37 has to be the final curly brace after return $weather; and this error has only occurred after creating a separate function for get_city(). I can move it back easy enough but I want to know:

Is it not possible to split this function up and what is the general opinion. Is what I’m trying to do pointless?

This function is pulling in a Yahoo XML weather feed which I process and output the data I require; which happens to be, the city, the temperature and the current conditions.

<?php

function get_current_weather_data() {
// Get XML data from source
$feed = file_get_contents("http://weather.yahooapis.com/forecastrss?p=USNY0996&u=f");

// Check to ensure the feed exists
if (!$feed) {
    die('Weather not found! Check feed URL');
}

$xml = new SimpleXmlElement($feed);

get_city(); 

// Pull temperature 
$weather['temp'] = $xml->channel->item->children('yweather', TRUE)->condition->attributes()->temp;
echo $weather['temp'] . "<br />";

// Pull current conditions 
$weather['conditions'] = $xml->channel->item->children('yweather', TRUE)->condition->attributes()->text;
echo $weather['conditions'] . "<br />";

return $weather;
}

get_city() function:

function get_city() {
// Pull city 
$weather['city'] = $xml->channel->children('yweather', TRUE)->location->attributes()->city;
echo $weather['city'] . "<br />";

}

Answer 1

This is a simple scoping and code design problem, nothing really to do with SimpleXML or XML.

You use $xml and $weather in your get_city() function, but it has no access to any variable $xml or $weather, nor any way to get that data back out!

Rewrite like so:

function get_city(SimpleXMLElement $xml) {
    // use your $xml to get the city value
    return $city;
}
// and in your get_current_weather_data() function, use like so:

$weather = array();
$weather['city'] = get_city($xml);