Print $_POST variable name along with value

If you want to detect array fields use a code like this:

foreach ($_POST as $key => $entry)
{
    if (is_array($entry)){
        print $key . ": " . implode(',',$entry) . "<br>";
    }
    else {
        print $key . ": " . $entry . "<br>";
    }
}

It's much better to use:

if (${'_'.$_SERVER['REQUEST_METHOD']}) {
    $kv = array();
    foreach (${'_'.$_SERVER['REQUEST_METHOD']} as $key => $value) {
        $kv[] = "$key=$value";
    }
}

If you just want to print the entire $_POST array to verify your data is being sent correctly, use print_r:

print_r($_POST);

To recursively print the contents of an array:

printArray($_POST);

function printArray($array){
     foreach ($array as $key => $value){
        echo "$key => $value";
        if(is_array($value)){ //If $value is an array, print it as well!
            printArray($value);
        }  
    } 
}

Apply some padding to nested arrays:

printArray($_POST);

/*
 * $pad='' gives $pad a default value, meaning we don't have 
 * to pass printArray a value for it if we don't want to if we're
 * happy with the given default value (no padding)
 */
function printArray($array, $pad=''){
     foreach ($array as $key => $value){
        echo $pad . "$key => $value";
        if(is_array($value)){
            printArray($value, $pad.' ');
        }  
    } 
}

is_array returns true if the given variable is an array.

You can also use array_keys which will return all the string names.

You can have the foreach loop show the index along with the value:

foreach ($_POST as $key => $entry)
{
     print $key . ": " . $entry . "<br>";
}

As to the array checking, use the is_array() function:

foreach ($_POST as $key => $entry)
{
     if (is_array($entry)) {
        foreach($entry as $value) {
           print $key . ": " . $value . "<br>";
        }
     } else {
        print $key . ": " . $entry . "<br>";
     }
}