Merging objects in PHP based on a property [duplicate] - php

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Merging and group two arrays containing objects based on one identifying column value
(4 answers)
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What I am originally trying to do is merge two objects
I have one object like this
{#23 ▼
+"Name": "Consultation"
+"ServiceId": "1024"
+"Price": ".00"
}
Another object
{#362 ▼
+"StartTime": "9:15AM"
+"ServiceId": "1024"
}
I am looking for a way to merge these two objects based on it's ServiceId, so I get a single object like this
{#1 ▼
+"Name": "Consultation"
+"ServiceId": "1024"
+"Price": ".00"
+"StartTime": "9:15AM"
}
Of course, if the ServiceId between the two objects do not match, it should not merge.
Any ideas on how to solve the error?

Answer 1

There seems to be two parts to your question. The first part is how to merge the output of two objects returned by json_decode. The second part is how to merge them only if the ServiceId match.
Part 1
json_decode produces, by default, objects of class \StdClass. If you want merge two \StdClass objects into a third \StdClass object, you need some judicious casting:
$a = json_decode('{"Name":"Consultation", "ServiceId":"1024", "Price":".00"}');
$b = json_decode('{"StartTime": "9:15AM", "ServiceId": "1024"}');
$c = (object)array_merge((array)$a, (array)$b);
var_dump($c);
Here, $a and $b are \StdClass objects. Cast them to array, merge, then cast them back to \StdClass.
That's a bit of a round-about way to go. So, you can benefit from working with these as arrays from the get-go. json_decode takes an optional second argument, which instructs it to return an array:
$a = json_decode('{"Name":"Consultation", "ServiceId":"1024", "Price":".00"}', true);
$b = json_decode('{"StartTime": "9:15AM", "ServiceId": "1024"}', true);
$c = array_merge($a, $b);
var_dump($c);
This works in arrays the whole time. If you later want $c to be a \StdClass object, you can cast it using $c = (object)$c; as was done in the first example.
See these live on 3v4l.org.
Part 2
Presumably, you're going to need some logic that iterates or otherwise pairs these objects together. You don't mention the source, but the logic will look something like this:
if ($a->ServiceId == $b->ServiceId) {
$c = (object)array_merge((array)$a, (array)$b)
}
If you have a list of objects, and you want to merge them all together, you can use the combinatoric array walk behavior of usort:
$merged = [];
usort($objects, function ($a, $b) use ($merged) {
$comp = strcmp($a->ServiceId, $b->ServiceId);
if (0 === $comp) {
$merged[] = (object)array_merge((array)$a, (array)$b)
}
return $comp;
});
var_dump($merged);
This iterates through your list of objects, comparing each. If the ServiceId match, then it merges the two objects and adds it to a list of merged. This will happen for as many objects that share ServiceId as you have in your list.

Answer 2

The idea here is too loop through 1 array and find the (assuming 1) element in the other array that match the current one:
foreach ($array1 as $key => $item) {
$other = array_filter($array2, function ($item2) use ($item) {
return $item2->ServiceId == $item->ServiceId;
});
if (!empty($other)) {
$item->StartTime = current($other)->SomethingElse;
}
}
Because you're dealing with objects merging all properties is a bit tricky.
Here's an example:
http://sandbox.onlinephpfunctions.com/code/15a9710dea77672c4ac4165044ad2c7aae4ae234