TYPO3 Core

if(!$content) {

$content = __json_encode($this->content);

}

function __json_encode( $data ) {

if( is_array($data) || is_object($data) ) {

$islist = is_array($data) && ( empty($data) || array_keys($data) === range(0,count($data)-1) );

if( $islist ) {

$json = '[' . implode(',', array_map('__json_encode', $data) ) . ']';

} else {

$items = Array();

foreach( $data as $key => $value ) {

$items[] = __json_encode("$key") . ':' . __json_encode($value);

}

$json = '{' . implode(',', $items) . '}';

}

} elseif( is_string($data) ) {

# Escape non-printable or Non-ASCII characters.

# I also put the \\ character first, as suggested in comments on the 'addclashes' page.

$string = '"' . addcslashes($data, "\\\"\n\r\t/" . chr(8) . chr(12)) . '"';

$json = '';

$len = strlen($string);

# Convert UTF-8 to Hexadecimal Codepoints.

for( $i = 0; $i < $len; $i++ ) {

$char = $string[$i];

$c1 = ord($char);

# Single byte;

if( $c1 <128 ) {

$json .= ($c1 > 31) ? $char : sprintf("\\u%04x", $c1);

continue;

}

# Double byte

$c2 = ord($string[++$i]);

if ( ($c1 & 32) === 0 ) {

$json .= sprintf("\\u%04x", ($c1 - 192) * 64 + $c2 - 128);

continue;

}

# Triple

$c3 = ord($string[++$i]);

if( ($c1 & 16) === 0 ) {

$json .= sprintf("\\u%04x", (($c1 - 224) <<12) + (($c2 - 128) << 6) + ($c3 - 128));

continue;

}

# Quadruple

$c4 = ord($string[++$i]);

if( ($c1 & 8 ) === 0 ) {

$u = (($c1 & 15) << 2) + (($c2>>4) & 3) - 1;

$w1 = (54<<10) + ($u<<6) + (($c2 & 15) << 2) + (($c3>>4) & 3);

$w2 = (55<<10) + (($c3 & 15)<<6) + ($c4-128);

$json .= sprintf("\\u%04x\\u%04x", $w1, $w2);

}

}

} else {

# int, floats, bools, null

$json = strtolower(var_export( $data, true ));

}

return $json;

}