PHP Adding element to multidimensional associative array (noob) - php

I have a multidimensional associative array that is made of of animals:
$animals = ["Cat"=>["name"=>"Junior","age"=>16],"Dog"=>["name"=>"Puppy","age"=>"Deceased"]];
I want to add a new animal to it. I know I can do this:
$animals["Lizard"]["name"]="Allen";
$animals["Lizard"]["age"]="Deceased";
But is there a way to do in in one statement, such as
$animals["Lizard"](["name"]="Eric",["age"]=>"Deceased");
Sorry I know this is a really dumb question but I'm a beginner. Thanks.

Just add entire array as an element:
$animals["Lizard"] = [ "name" => "Eric", "age" => "Deceased" ];
or
$animals["Lizard"] = array( "name" => "Eric", "age" => "Deceased" );
Manual (look at example #6).

Related

Pushing array into multidimensional array (php) [duplicate]

This question already has an answer here:
array_push won't give an array, prints out integer value
(1 answer)
Closed 4 years ago.
I've attempted many different ways to push an array into a multidimensional array, including array_push(), $array['index'] = $toPush but I keep being met with quite unexpected results. I have used both var_dump() and print_r() as detailed below in an attempt to debug, but cannot work out the issue.
My reasoning behind is to run a while loop to pull game id's and game names and store these in an assoc. array, and then push them into my main array.
$games_array = array
(
"games" => array
(
array("id"=>"1", "game"=>"first game");
array("id"=>"2", "game"=>"second game");
)
);
// a while loop would run here and update $game_to_add;
$game_to_add = array("id"=>"$game['id']", "game"=>"$game['title']");
$games_array = array_push($games_array['games'], $game_to_add);
In this example, the while() would update the ID and the Game inside of $game_to_add
But, whenever I attempt this it simply overwrites the array and outputs an integer ( example: int(3) )
I don't understand what the problem is, any explination would be appreciated as I cannot find a question specifically for this.
My actual test code:
$games_array = array( "games" => array(
array("id" => "1", "name" => "Star feathers"),
array("id" => "2", "name" => "chung fu")
)
);
$another_game = array("id" => "3", "name" => "some kunt");
$games_array = array_push($games_array["games"], array("id" => "3", "name"
=>"some game"));
var_dump($games_array);
You're assigning the return value of array_push to the games array.
The return value of array_push is the amount of elements after pushing.
Just use it as
array_push($array, $newElement);
(Without assignment)
If you're only pushing one element at he time, $array[] = $newElement is preferred to prevent overhead of the function call of array_push

Multidimensional array loop with array search

I realize there are a number of questions about multidimensional arrays and foreach loops, and I have spent hours reading through them and trying to get my own loop to work -- without success. If the solution is a duplicate, I'll remove my question (or link to another if that is preferred).
Now, the challenge:
Using an array of returned MYSQL results. The results are from multiple joined tables in an associative array. Now I need to convert it to the multidimensional array I need.
I've got most of it working, but my issue is looping through and adding new items to the right place in the array.
Here's some code:
//example of how array is setup in the way I want, this part works.
foreach($results as $i => $a):
//some other code is here, see below.
$items[$i] = [
"id" => $a['id'],
"itemid" => $a['itemid'],
"name" => $a['name'],
"def" => $a['def'],
"class" => $a['class'],
"timeline" => $a['timeline'],
"files" => [
[0] => [
"id" => $a['fileid'],
"name" => $a['filename'],
"path" => $a['filepath'],
"type" => $a['filetype']
]
],
"tags" => [
[0] => [
"id" => $a['tagid'],
"name" => $a['tagname']
]
]
];
endforeach;
Then I've tried a number of ways to loop through in order to only add to the 'tags' or 'files' if the item 'id' is the same as the last. Here is the current code in my editor, not working:
//inside foreach loop, before above code
if($items[$i-1]['id'] == $a['id']):
//it is the same item, works to here.
if(in_array($a['filename'], $items[$i-1], FALSE)):
//add to files array for last item
$items[$i-1]['files'][] = [
"id" => $a['fileid'],
"name" => $a['filename'],
"path" => $a['filepath'],
"type" => $a['filetype']
];
elseif(in_array($a['tagname'], $items[$i-1], FALSE)):
//add to tags array for last item
$items[$i-1]['tags'][] = [
"id" => $a['tagid'],
"name" => $a['tagname']
];
endif;
else:// else it does the code above
As you can see, my most recent attempt was to use in_array, which I now realize doesn't work on multidimensional arrays. My issue is that I can't figure out how to determine if its a new file or new tag for the same item.
Ultimately, I want an array of 'items' which have multiple 'files' and 'tags.' I'm going to json_encode and use it with JS afterwards.
Any advice on how to get this working or optimize it, would be greatly appreciated.
P.S. As I mentioned above, I know this question has been asked before -- though I wasn't able to get their solutions working for me. I'll remove this question if the solution is a duplicate (as in, it's not really helpful to others). Thank you for any help, it is greatly appreciated!
Don't use "autoincrementing" array indices as they easily get messed up. Use your database id since it's already there:
//example of how array is setup in the way I want, this part works.
foreach($results as $i => $a):
$items[$a['id']] = [ // THIS CHANGED.
"id" => $a['id'],
"itemid" => $a['itemid'],
...
Now, with any further result, you can easily check, if the id is already in your array:
if (isset($items[$a['id']])) {
// We had this id before, just add files/tags to it.
// Check first, if files subarray exists, if not: create it.
if (!isset($items[$a['id']]['files'])) {
$items[$a['id']]['files'] = array();
}
$items[$a['id']]['files'][] = array(...); // add the new file.
// Repeat for tags.
}
If your result could return the same file more than once for an id, you can check if the filename is already in there by using a search function:
$filename = $a['filename'];
if (!searchFilename($filename, $items[$a['id']]['files']) {
// Filename is not in there, yet.
// Add file info.
}
function searchFilename($id, $array) {
foreach ($array as $key => $val) {
if ($val['filename'] === $id) {
return true;
}
}
return false;
}
Same applies to tags in a similar way.
In the end, if you do not want the ids for index of $items, just call:
$items = array_values($items);

PHP Definition MultiDimensional Associative Arrays

I have 2 arrays with some sample data and I just want to confirm if I have the terminology correct:
Multidimensional Array:
$names = array([
"name" => "Bob",
"age" => 25,
"level" => 6],
["name" => "Joe",
"age" => 34,
"level" => 6]
);
Multidimensional Associative Array:
$names = array(
"Bob" => array(
"age" => 25,
"diploma" => "DAC",
"level" => 6),
"Joe" => array(
"age" => 34,
"diploma" => "DAC",
"level" => 6)
);
The second is Associative because of the index being the name rather than an index number and MultiDimensional because it has more than one entry.
I know it is not really a programming question requiring a code solution, I am just learning the terminology.
I add my two cents. All said by others is pretty correct, but:
The main difference from associative arrays and "simple" arrays. With "simple" arrays you can do something like this
for( $i = 0; $i < count( $array ) - 1; $i++ ) {
$element = $array[ $i ];
// Do something with $element
}
With associative arrays, you cannot do it and, if you want to traverse all the arrays you have to do something like this
foreach( $array as $key => $element ) {
// Do something with $element
}
This approach (the foreach) can be applied to the "simple" array too, while the first can be applied ONLY to "simple" array
Multidimensional array are simply arrays with AT LEAST one element that is an array, no matter the "type"
By the way, it's always think about arrays as associative arrays, always. It prevents you some very simple mistakes later on
Both arrays are multidimensional associative array.
But in second array you can get details of Bob or Joe by just using their name as key. For example to get details of Bob you can just call:
$names['Bob']
In first array you have to know the id or index of array to which Bob details were stored.

Best way to refer index which contains in array

In php I'm willing to check the existence of indexes that match with another values in array.
$indexes = array("index", "id", "view");
$fields = array(
"index" => 5,
"id" => 7,
"form" => 10,
"date" => 10,
);
MY ideal result is, in this case, to get "form" and "date". Any idea?
Try
$fields_keys = array_keys($fields);
$fields_unique = array_diff($fields_keys, $indexes);
The result will be an array of all keys in $fields that are not in $indexes.
You can try this.
<?php
$indexes = array("index", "id", "view");
$fields = array(
"index" => 5,
"id" => 7,
"form" => 10,
"date" => 10,
);
$b = array_diff(array_keys($fields), $indexes);
print_r($b);
You can use array_keys function to retrieve keys of a array
Eg:
$array = array(0 => 100, "color" => "red");
print_r(array_keys($array));
Outputs
Array
(
[0] => 0
[1] => color
)
PHP Documentation
Your question is a little unclear but I think this is what you're going for
array_keys(array_diff_key($fields, array_fill_keys($indexes, null)));
#=> Array( 0=>"form", 1=>"date" )
See it work here on tehplayground.com
array_keys(A) returns the keys of array A as a numerically-indexed array.
array_fill_keys(A, value) populates a new array using array A as keys and sets each key to value
array_diff_key(A,B) returns an array of keys from array A that do not exist in array B.
Edit turns on my answer got more complicated as I understood the original question more. There are better answers on this page, but I still think this is an interesting solution.
There is probably a slicker way than this but it will get you started:
foreach(array_keys($fields) as $field) {
if(!in_array($field, $indexes)) {
$missing[] = $field;
}
}
Now you will have an array that holds form and date.

Transform string from associative array into multidimensional array

I'm storing images links into the database separating them with ,, but I want to transform this string into an array, but I'm not sure how to do it.
So my array looks like this:
$array = array(
"name" => "Daniel",
"urls" => "http:/localhost/img/first.png,http://localhost/img/second.png"
);
So I'd like to have it in the following form:
$array2 = array(
"name" => "Daniel",
"urls" => array("http:/localhost/img/first.png",
"http://localhost/img/second.png" )
);
I haven't been PHP'ing for a while, but for that simple use-case I would use explode.
$array['urls'] = explode(',', $array['urls']);
Uncertain if I interpreted your question correct though?
You can use array_walk_recursive like in the following example.
function url(&$v,$k)
{
if($k=='urls') {
$v = explode(",",$v);
}
}
$array = array(
"name" => "Daniel",
"urls" => "http:/localhost/img/first.png,http://localhost/img/second.png"
);
array_walk_recursive($array,"url");
You can check the output on PHP Sandbox

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