SimpleXML, iteration on all element - php

I have a stock report file (coming from an outer source, therefore I can't modify in any way) and I would like to iterate over all elements (I have to save them into a MySQL table). As I see the $xml->Stockfile is an array of objects (2 items), so I tried to put it into an array.
For some reason the $myarray contains only the first element after the $myarray = $xml->StockFile assignment.
here is my code:
$xml = simplexml_load_file("../docs/stock.xml");
print_r($xml);
$myarray = $xml->StockFile;
print_r($myarray);
stock.xml:
<NewDataSet>
<StockFile>
<MatrixID>1533</MatrixID>
<Brand>myBrand</Brand>
<ProductCode>001</ProductCode>
<RRP>29.99</RRP>
<Image2Name />
<Image3Name />
</StockFile>
<StockFile>
<MatrixID>1534</MatrixID>
<Brand>myBrand</Brand>
<ProductCode>002</ProductCode>
<RRP>29.99</RRP>
<Image2Name />
<Image3Name />
</StockFile>
</NewDataSet>
Why I'm getting only one item instead of all?
What should I do do retrieve the whole array?

Take care with SimpleXMLElement. It has a lot of magic. Know the magic or get puzzled by print_r or var_dump or similar output. Your example extended:
$myarray = $xml->StockFile;
print_r($myarray); # shows one element
# foreach has both elements:
foreach($myarray as $name => $stockfile)
{
echo $name, ":\n", $stockfile->asXML(), "\n\n";
}
Even though it is the same variable ($myarray) it behaves differently depending on context it is used in. Inside a foreach the SimpleXMLElement (that is the type of that object) will provide an iterator over the child-elements named StockFile as specified here:
$myarray = $xml->StockFile;
However using that variable in some kind of single context, it will for example return the inner string of the first child-element with that name:
echo $myarray, "\n";
(which in your case is just some lines of whitespace).
See Demo: https://eval.in/83787
Running into this "trap" by SimpleXML is actually pretty common. I suggest to understand the basic usage by the example given in the manual:
Basic SimpleXML usage

change the last two lines to
foreach ($xml->StockFile as $nextStockFile) {
print_r ($nextStockFile);
}

Related

Finding titles in JSON

I currently have this large JSON file: hastebin
But just want the titles of the posts.
I've tried this...
$json = $page;
$o = json_decode($json, true);
echo($json);
$titles = $o["*"]["*"]["*"]["*"]["title"];
var_dump($titles);
But it isn't working - it's returning NULL! Sometimes it just doesn't return anything.
If anyone is wondering, yes this is from Reddit.
This should do it:
$titles = array_map(function($post) {
return $post['data']['title'];
}, $o['data']['children']);
I'm not sure what you expected using "x" indices, but you should probably read about arrays.
PHP can't use wildcards like * in array keys. Whatever string you use to reference the key, it's going to try to find a key with that exact string. So what you tried can't work because there aren't any * keys.
You can get it by iterating all the levels, or iterating the outer level and referring to the proper nested key. But if you're just looking for all instances of 'title' a recursive method may be an easier way to get them.
array_walk_recursive($o, function($value, $key) use (&$titles) {
if ($key == 'title') $result[] = $value;
});
var_dump($titles);
This will get any value of 'title' regardless of its depth in the array, so if that's not what you want, then you'll need to iterate it and specifically reference the proper ones.
It's very hard to deal directly with such a long JSON document. The returned result from the page is not a valid JSON. It contains some HTML tags, but if you take the posts data and insert it in a file you can do the following according to the structure of your JSON (You can find your JSON in an external link here):
<?php
header("Content-Type:application/json");
$posts=file_get_contents('json.php');
//decode your JSON STRING
$posts=json_decode($posts,true);
//create a title variable to store your titles
$titles=array();
foreach($posts['data']['children'] as $child)
{
array_push($titles,$child['data']['title']);
}
echo json_encode($titles);
?>
You can even use this approach using a URL but ensure that it will return a valid JSON with no html

Access JSON values in PHP

{"coord":{"lon":73.69,"lat":17.8},"sys":{"message":0.109,"country":"IN","sunrise":1393032482,"sunset":1393074559},"weather":[{"id":800,"main":"Clear","description":"Sky is Clear","icon":"01n"}],"base":"cmc stations","main":{"temp":293.999,"temp_min":293.999,"temp_max":293.999,"pressure":962.38,"sea_level":1025.86,"grnd_level":962.38,"humidity":78},"wind":{"speed":1.15,"deg":275.503},"clouds":{"all":0},"dt":1393077388,"id":1264491,"name":"Mahabaleshwar","cod":200}
I am trying to fetch description from the weather from the json above but getting errors in php. I have tried the below php code:
$jsonDecode = json_decode($contents, true);
$result=array();
foreach($jsonDecode as $data)
{
foreach($data{'weather'} as $data2)
{
echo $data2{'description'};
}
}
Any help is appreciated. I am new in using json.
You have to use square brackets ([]) for accessing array elements, not curly ones ({}).
Thus, your code should be changed to reflect these changes:
foreach($data['weather'] as $data2)
{
echo $data2['description'];
}
Also, your outer foreach loop will cause your code to do something completely different than you intend, you should just do this:
foreach($jsonDecode['weather'] as $data2)
{
echo $data2['description'];
}
Your $jsonDecode seems to be an array, so this should work-
foreach($jsonDecode['weather'] as $data)
{
echo $data['description'];
}
You can access data directly with scopes
$json = '{"coord":{"lon":73.69,"lat":17.8},"sys":{"message":0.109,"country":"IN","sunrise":1393032482,"sunset":1393074559},"weather":[{"id":800,"main":"Clear","description":"Sky is Clear","icon":"01n"}],"base":"cmc stations","main":{"temp":293.999,"temp_min":293.999,"temp_max":293.999,"pressure":962.38,"sea_level":1025.86,"grnd_level":962.38,"humidity":78},"wind":{"speed":1.15,"deg":275.503},"clouds":{"all":0},"dt":1393077388,"id":1264491,"name":"Mahabaleshwar","cod":200}';
$jsonDecode = json_decode($json, true);
echo $jsonDecode['weather'][0]['description'];
//output Sky is Clear
As you can see wheater` is surrounded with scopes so that means it is another array. You can loop throw that array if you have more than one result
foreach($jsonDecode['weather'] as $weather)
{
echo $weather['description'];
}
Live demo
If the result of decode is an array, use:
$data['weather']
If the result is an object, use:
$data->weather
you have to access "weather" with "[]" operator
like this,
$data["weather"]
There is several things worth answering in your question:
Q: What's the difference between json_decode($data) and json_decode($data, true)?
A: The former converts JSON object to a PHP object, the latter creates an associative array: http://uk1.php.net/json_decode
In either case, there is no point on iterating over the result. You probably want to access just the 'weather' field:
$o = json_decode($data) => use $weather = $o->weather
$a = json_decode($data, true) => use $weather = $a['weather']
Once you have the 'weather' field, look carefully what it is:
"weather":[{"id":800,"main":"Clear","description":"Sky is Clear","icon":"01n"}]
It's an array, containing a single object. That means you will either need to iterate over it, or use $clearSky = $weather[0]. In this case, it does not matter which approach of json_decode did you choose => JSON array is always decoded to a PHP (numeric indexed) array.
But, once you get $clearSky, you are accessing the object and it again matters, which approach you chose - use arrow or brackets, similarly to the first step.
So, the correct way to get for exaple the weather description would be either of these:
json_decode($data)->weather[0]->description
json_decode($data, true)['weather'][0]['description']
Note: In the latter case, dereferencing result of the function call is supported only in PHP 5.4 or newer. In PHP 5.3 or older, you have to create a variable.
Note: I also encourage you to always check if the expected fields are actually set in the result, using isset. Otherwise you will try to access undefined field, which raises an error.

In PHP, filter an Array of Associative Arrays

In PHP, are there any inbuilt functions to turn
[{"id":1, "name":"John"}, {"id":2, "name":"Tim"}]
into
[{"id":1}, {"id":2}]
?
I've used JSON to describe the objects above, but that's just a conceptual representation of my array of associative arrays. I don't want to have to loop manually - something short and elegant I can fit on one line would be nice.
One line, using array_map:
$arr = json_decode('[{"id":1, "name":"John"}, {"id":2, "name":"Tim"}]');
$new_arr = array_map(function($el){$ret=array("id"=>$el->id);return $ret;},$arr);
var_dump(json_encode($new_arr));
array_map(function($arr){return $arr[0];}, $array);
This should do it.
Edit As noted by Jonathon Hibbard, you could pass array element by reference, this way you do not to assign result of the function and just use changed old array. The code should then be modified appropriately.
First decode json by json_decode. You will get an array. Then follow this link to remove an index from an associative array. Then again decode it. It should work.
do something like:
$array = json_decode($some_json_string, true);
array_walk($array, function($value, $key) use(&$array) {
if($key == "name") {
unset($array[$key]);
}
});
Edit:
Cthulhu's answer won't get ya there without re-assigning it. Could use it as a reference though (equal to the walk. though if you want to use the map, its a bit better not to reallocate with a brand new array copy and just pass it by reference, then remove the key with an unset within it and move on.)
array_map(function(&$array) { unset($array['name']; }, $array);

reading the first value using simplexml

I am using simplexml to read all the child nodes successfully. But how do I read the "NumCrds"?
<ACCOUNT NumCrds="1">
<ACCNO>some Bank</ACCNO>
<CURRCODE>CAD</CURRCODE>
<ACCTYPE>00</ACCTYPE>
</ACCOUNT>
I have read it somewhere in the PHP manual but I am unable to find it now.
$my_num_cards=$sxe->ACCOUNT['NumCrds'];
This is printing the number 1 for all the records even if there are values like 2, 3 in the file.
Attributes can be accessed using array indexes:
$data = '<ACCOUNT NumCrds="1">
<ACCNO>some Bank</ACCNO>
<CURRCODE>CAD</CURRCODE>
<ACCTYPE>00</ACCTYPE>
</ACCOUNT>
';
$xml = new SimpleXMLElement($data);
// this outputs 1
echo $xml['NumCrds'];
It is also possible to use the SimpleXMLElement::attributes() function to returns a list of all of the attribute key/value pairs.
$attributes = $xml->attributes();
echo $attributes['NumCrds'];
Use either $attrs = $el->attributes(); echo $attrs['NumCrds'] or just echo $el['NumCrds']. Attributes are reflected as array elements, while sub-tags are reflected as object properties.
$my_num_cards=$item->attributes()->NumCrds;
This is what I was looking for. Thanks for all your help.
http://fr.php.net/manual/en/simplexmlelement.attributes.php#94433

php arrays (and removing certain element)

I'm not 100% but this ($settings) would be called an array in php:
$setting;
$setting['host'] = "localhost";
$setting['name'] = "hello";
but what's the name for this that's different to the above:
$settings = array("localhost", "hello");
Also from the first example how can i remove the element called name?
(please also correct my terminology if I have made a mistake)
I'm not 100% but this ($settings)
would be called an array in php:
You should be 100% sure, they are :)
but what's the name for this that's
different to the above:
This:
$setting['host'] = "localhost";
$setting['name'] = "hello";
And this are different ways of declaring a php array.
$settings = array("localhost", "hello");
In fact this is how later should be to match the first one with keys:
$settings = array("host" => "localhost", "name" => "hello");
Also from the first example how can i
remove the element called name?
You can remove with unset:
unset($setting['name']);
Note that when declaring PHP array, do:
$setting = array();
Rather than:
$setting;
Note also that you can append info to arrays at the end by suffixing them with [], for example to add third element to the array, you could simply do:
$setting[] = 'Third Item';
More Information:
http://php.net/manual/en/language.types.array.php
As sAc said, they are both array. The correct way to declare an array is $settings = array(); (as opposed to just $settings; in your first line.)
The main difference between the first and second way is that the first allows you to use $settings['host'] and $settings['name'], whereas the latter can only be used with numeric indices ($settings[0] and $settings[1]). If you want to use the first way, you can also declare your array like this: $settings = array('host'=>'localhost', 'name'=>'hello');
More reading on PHP arrays
Well this is indeed an array. You have different types of array's in php. The first example you mention is called an Associative Array. Simply an array with a string as a key.
An associative array can be declared in two ways:
1) (the way you declared it):
$sample = array();
$sample["name"] = "test";
2)
$sample = array("name" => "localhost");
Furthermore the first example can also be used to add existing items to an array. For example:
$sample["name"][] = "some_name";
$sample["name"][] = "some_other_name";
When you execute the above code with print_r($sample) you get something like:
Array ( [name] => Array ( [0] => some_name [1] => some_other_name ) )
Which is very usefull when adding multiple strings to an existing array.
Removing a value from an array is very simple,
Like mentioned above, use the unset function.
unset($sample["name"])
to unset the whole name value and values connected to it
Or when you only want to unset a specific item within $sample["name"] :
unset($sample["name"][0]);
or, ofcourse any item you'd like.
So basicly.. the difference between your first example and the latter is that the first is an associative array, and the second is not.
For further reference on arrays, visit the PHP manual on arrays

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