PHP: Convert Multidimensional Array to String - php

Question

I am trying to convert a multidimensional array into a string.
Till now I have been able to convert a pipe delimited string into an array.
Such as:
group|key|value
group|key_second|value
Will render into the following array:
$x = array(
'group' => array(
'key' => 'value',
'key_second' => 'value'
),
);
However, now I want it to be the other way around, where a multidimensional array is provided and I want to convert it to a pipe delimited string just like in the first code example.
Any ideas how to do this ?
PS: Please do note that the array can dynamically have any depth.
For example:
$x['group']['sub_group']['category']['key'] = 'value'
Translates to
group|sub_group|category|key|value

Answer 1

I have created my own function:
This should have no problem handling even big arrays
function array_to_pipe($array, $delimeter = '|', $parents = array(), $recursive = false)
{
$result = '';
foreach ($array as $key => $value) {
$group = $parents;
array_push($group, $key);
// check if value is an array
if (is_array($value)) {
if ($merge = array_to_pipe($value, $delimeter, $group, true)) {
$result = $result . $merge;
}
continue;
}
// check if parent is defined
if (!empty($parents)) {
$result = $result . PHP_EOL . implode($delimeter, $group) . $delimeter . $value;
continue;
}
$result = $result . PHP_EOL . $key . $delimeter . $value;
}
// somehow the function outputs a new line at the beginning, we fix that
// by removing the first new line character
if (!$recursive) {
$result = substr($result, 1);
}
return $result;
}
Demo provided here http://ideone.com/j6nThF

Answer 2

You can also do this using a loop like this:
$x = array(
'group' => array(
'key' => 'value',
'key_second' => 'value'
)
);
$yourstring ="";
foreach ($x as $key => $value)
{
foreach ($x[$key] as $key2 => $value2)
{
$yourstring .= $key.'|'.$key2.'|'.$x[$key][$key2]."<BR />";
}
}
echo $yourstring;
Here is a working DEMO

Answer 3

This code should do the thing.
You needed a recursive function to do this. But be careful not to pass object or a huge array into it, as this method is very memory consuming.
function reconvert($array,$del,$path=array()){
$string="";
foreach($array as $key=>$val){
if(is_string($val) || is_numeric($val)){
$string.=implode($del,$path).$del.$key.$del.$val."\n";
} else if(is_bool($val)){
$string.=implode($del,$path).$del.$key.$del.($val?"True":"False")."\n";
} else if(is_null($val)){
$string.=implode($del,$path).$del.$key.$del."NULL\n";
}else if(is_array($val)=='array') {
$path[]=$key;
$string.=reconvert($val,$del,$path);
array_pop($path);
} else {
throw new Exception($key." has type ".gettype($val).' which is not a printable value.');
}
}
return $string;
}
DEMO: http://ideone.com/89yLLo

Answer 4

You can do it by
Look at serialize and unserialize.
Look at json_encode and json_decode
Look at implode
And Possible duplicate of Multidimensional Array to String

Answer 5

You can do this if you specifically want a string :
$x = array(
'group' => array(
'key' => 'value',
'key_second' => 'value'
),
'group2' => array(
'key2' => 'value',
'key_second2' => 'value'
),
);
$str='';
foreach ($x as $key=>$value)
{
if($str=='')
$str.=$key;
else
$str.="|$key";
foreach ($value as $key1=>$value1)
$str.="|$key1|$value1";
}
echo $str; //it will print group|key|value|key_second|value|group2|key2|value|key_second2|value