Remove JSON array index that holds specific value with PHP - php

Question

I am brand new to php.I have found questions that show how to remove key/value pairs from JSON files with php, but not array indexes.
I have worked out how to append values to arrays in a JSON file with json_decode(). But not how to remove values. I need to produce a function() that hunts for c and removes any value within an array in my JSON file. Below is a before and after of the expected outcome I need to produce with my php file.
// before
[["a", "c", "b"], ["c", "c"], [], ["c", "d"], ["d"], ["e"]]
// after
[["a", "b"], [], [], ["d"], ["d"], ["e"]]
Below is the function I have produced in order to add values to arrays in my JSON if this helps provide more context:
function appendClient($file, $post, $client) {
$a = fopen($file, "r");
$json = json_decode(fread($a, filesize($file)));
$json[$post][] = $client;
fclose($a);
$a = fopen($file, "w");
fwrite($a, json_encode($json));
fclose($a);
}

Answer 1

Use array_filter
function removeClient($file, $post, $client) {
$json = json_decode(file_get_contents($file));
$json[$post] = array_filter($json[$post], function($x) use($client) {
return $x != $client;
});
file_put_contents($file, json_encode($json));
}
This assumes all the elements of the array are either empty arrays or 1-element arrays containing the client name, as in the example you showed.

Answer 2

Take a look at array_filter and array_values functions.
[["a"],[],["b"],["c"]]
From the above input, I am assuming you are working with 2d array. Then, you can use the following function to do the job:
function removeValues($array, $value) {
$result = [];
foreach ($array as $row) {
$filtered = array_filter($row, function($entry) use($value) {
return $entry != $value;
});
// If you need to reset keys
$filtered = array_values($filtered);
$result[] = $filtered;
}
return $result;
}
Example:
$input = [["a"],[],["b"],["c"]];
$output = removeValues($input, "c");
print_r($output);