php add items using an multi dimentional array

Question

I have multi-dimensional array like this:

Array
(
    [0] => Array
        (
            [id] => 10184            
            [user_tags] => tag1
         )
)

how do i add more 'user_tags' with comma seperated in an array using php

Thanks

Answer 1

 $arr[0]['user_tag'] .= ','.$valueToAdd;

要么

$arr[0]['user_tag'] .= ','.implode(',', $valueToAdd); // if its an array

Answer 2

You can add something to your 'user_tags' like this :

$myarray[0]['user_tags'] = 'whatever';

If you have an array of tags like this, you can add it like that :

$tags = array('tag1', 'tag2', 'tag3', 'tag4');
$myarray[0]['user_tags'] = implode(', ', $tags);

But in this case, it is maybe better to store the array directly like said in another comment.

If you want to just add one tag :

$myarray[0]['user_tags'] .= ', '.$mytag;

Answer 3

As a hint, I wouldn't store the usertags in comma separated style, but rather in another array, so that $myArray['user_tags'] = array('tag1, 'tag2', 'tag3', ...); .

You can then translate between array and csv like this:

$myArray['user_tags_csv'] = implode(',', $myArray['user_tags']);
$myArray['user_tags'] = explode(',', $myArray['user_tags_csv']);

This makes it easier to search the tags for existing ones before you append one.

I use this a lot (esp. with user tags or flags) in connection with an SQL database. With different separators (eg ',' ';' '|') I even create hierarchical csv strings which translate into multi-dimensional arrays.

Pro-tip: Store the tags in an associative array like {'tag1'='tag1', 'tag2'='tag2'} , create it with

$myArray['user_tags'] = array_combine(explode(',', $myArray['user_tags_csv']), explode(',', $myArray['user_tags_csv']);

Then you can use array_key_exists() as well as array_search() and many other neat things. I use that a lot.