user_error('Connection closed by server',E_USER_NOTICE);

它会触发错误.您可以使用http://php.net/manual/en/function.set-error-handler.php处理这些错误

例如

// Your file.PHP
$ssh = new Net_SSH2('10.199.1.7');        
$ssh->login('deploy',$key);
 
// bootstrap.PHP
// This will catch all user notice errors!!!
set_error_handler ('errorHandler',E_USER_NOTICE)
 
function errorHandler($errno,$errstr,$errfile,$errline) {
    echo 'Error';
    // Whatever you want to do.
}