How to create new arrays from object array based on user_id? - php

Question

I'm having trouble looping through an object array and displaying data from it under certain conditions.
I want the webpage to display the following:
<p>John Doe</p> <p>William Green</p> <p>Jane Smith</p>
I know how to do this by defining $user[0]->first_name . $user[0]->last_name specifically, but what I need is a way for the code to loop through and display the names dynamically using the user_id property as a unique identifier.
For all objects in the array with user_id 1, return "these values." For all the objects in the array with user_id 2, return "these values." And so on...looping through each unique user_id.
Here is a var_dump of the object array:
array(4)
{ [0]=> object(stdClass)#4336 (4)
{
["umeta_id"]=> string(1) "1"
["user_id"]=> string(1) "1"
["meta_key"]=> string(10) "first_name"
["meta_value"]=> string(4) "John"
}
[1]=> object(stdClass)#4333 (4)
{
["umeta_id"]=> string(1) "2"
["user_id"]=> string(1) "1"
["meta_key"]=> string(9) "last_name"
["meta_value"]=> string(3) "Doe"
}
[2]=> object(stdClass)#4334 (4)
{
["umeta_id"]=> string(1) "3"
["user_id"]=> string(1) "2"
["meta_key"]=> string(10) "first_name"
["meta_value"]=> string(4) "Jane"
}
[3]=> object(stdClass)#4334 (4)
{
["umeta_id"]=> string(1) "4"
["user_id"]=> string(1) "2"
["meta_key"]=> string(9) "last_name"
["meta_value"]=> string(5) "Smith"
}
[4]=> object(stdClass)#4334 (4)
{
["umeta_id"]=> string(1) "5"
["user_id"]=> string(1) "3"
["meta_key"]=> string(10) "first_name"
["meta_value"]=> string(7) "William"
}
[5]=> object(stdClass)#4334 (4)
{
["umeta_id"]=> string(1) "6"
["user_id"]=> string(1) "3"
["meta_key"]=> string(9) "last_name"
["meta_value"]=> string(5) "Green"
}
}
When I output the information on the webpage, I want it to look like this:
<p>John Doe</p> <p>William Green</p> <p>Jane Smith</p>
Maybe I need to loop through objects and build new arrays based on user_ids? Please do not provide code with echo or print_r. Only "return" can be used for this project.

Answer 1

So $your_object is already sorted by umeta_id and user_id fields?
If not, you can use usort:
function cmp1($a, $b)
{
return strcmp($a->umeta_id, $b->umeta_id);
}
function cmp2($a, $b)
{
return strcmp($a->user_id, $b->user_id);
}
usort($your_object, "cmp1");
usort($your_object, "cmp2");
Then simply:
$str = '';
for($i=0;$i<count($your_object);$i+=2){
$str .= "<p>".$your_object[$i]->meta_value." "$your_object[$i+1]->meta_value."</p> ";
}
return $str; // this var contain all your data in string
Hope this helps!

Answer 2

This will generate the first-name and last-name pairs :
$user_group = array();
ksort($user_group, SORT_NUMERIC);
foreach ($users as $key => $item) {
$name_meta = get_object_vars($item);
foreach ($name_meta as $meta_in => $names) {
if ($names == 'first_name') {
$user_group[$item->user_id]['first_name'] = $name_meta['meta_value'];
}
if ($names == 'last_name') {
$user_group[$item->user_id]['last_name'] = $name_meta['meta_value'];
}
}
}
Output :
array(3) {
[1]=>
array(2) {
["first_name"]=>
string(4) "John"
["last_name"]=>
string(3) "Doe"
}
[2]=>
array(2) {
["first_name"]=>
string(4) "Jane"
["last_name"]=>
string(5) "Smith"
}
[3]=>
array(2) {
["first_name"]=>
string(7) "William"
["last_name"]=>
string(5) "Green"
}
}
And to print the user name pairs :
foreach ($user_group as $name) {
echo "<p>" . $name['first_name'] . " " . $name['last_name'] . "</p>";
}