PDO OCI：信息例外成功

Using PHP 5.5.9 with PDO_OCI, Oracle 12.1. I'm getting an OCI_SUCCESS_WITH_INFO message that the password will expire soon. However, since it is thrown as an exception by PDO, the connection is not being established. How can I ignore the exception when it is just a warning or informational message?

Here is the error message:

Database Connection failed: SQLSTATE[HY000]: OCISessionBegin: OCI_SUCCESS_WITH_INFO: ORA-28002: the password will expire within 41 days

Followed by:

Fatal error: Call to a member function setAttribute() on a non-object in /htdocs/ciatools_dev/promise/Classes/PromiseVars.php on line 257

And the code that produces it:

try {
    $this->dbconn = new PDO("oci:dbname=$dbwc",'username', 'password');
} catch (PDOException $e) {
    echo 'Database Connection failed: ' . $e->getMessage();
}

$this->dbconn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

If this is a test system try changing the password of the user to see if resolves the error message. This thread has more details

alter user <your user> identified by password;

You could also alter the profile of that user so it does not expire which is acceptable on development but a security issue on production.

--get the the profile 
SELECT profile FROM dba_users WHERE username = <'Your user'>;
--change the profile
ALTER PROFILE <this user's profile> LIMIT PASSWORD_LIFE_TIME UNLIMITED;