Phalcon PHP Ajax错误模型

When i'm trying to save my model like this if( !$myModel->save() ) I have to surround in try catch my condition if I want to get the errors messages... I can't check if the save() is false, because this will not returns the errors.

How can I do to get $myModels->getMessages() without using try catch ?

I want to do like this example and return json_encode if the save doesn't work.

The example from the docs, shows you how to get the messages after you save your $myModel

$robot       = new Robots();
$robot->type = "mechanical";
$robot->name = "Astro Boy";
$robot->year = 1952;

if ($robot->save() == false) {
    echo "Umh, We can't store robots right now: 
";
    // get the messages of the saved Robot.
    foreach ($robot->getMessages() as $message) {
        echo $message, "
";
    }
} else {
    echo "Great, a new robot was saved successfully!";
}