[php]
<?php
/*
foreach (array_keys($_POST) as $field)
{
echo $_POST[$field];
}
*/
$jsonString="{";
$i=0;
foreach ($_POST as $name => $val)
{
try {
if($i>0){$jsonString=$jsonString.",";}
$i=$i+1;
if ( is_array( $val ) == true ) {
$jsonString = $jsonString."\"" . $name . "\":" . json_encode($val) . "";
} else {
if(is_numeric($val)){
$jsonString = $jsonString."\"" . $name . "\":" . $val . "";
}else{
$jsonString = $jsonString."\"" . $name . "\":\"" . $val . "\"";
}
// echo htmlspecialchars( $name . ‘: ‘ . $val ) . "<br>\n";
}
}catch (Exception $e) {
}
}
$jsonString=$jsonString."}";
echo $jsonString;

?>
[/php]
output:

{“aaa”:”123@gmail.com”,”bbb”:”asds”,”cccc”:””,”dddd”:[“cccc”]}