好的，我有下面的php，它运行正常，直到IF，但无论我做什么，我都无法让bp\\U核心消息在屏幕上激发，它只会给我保存的更改消息。。。为什么我做错了什么！

    function valid_postcode ($self) {
    $getFieldID = $self->field_id;
    $PostCodeFieldID = 23;
    $postcodecheck = $_POST[\'field_23\'];
 if ( $getFieldID == $PostCodeFieldID || $postcodecheck == \'\'){

        $GetValuePost = $self->value;

        $regex = \'/[a-z][0-9][a-z][- ]?[0-9][a-z][0-9]$/i\';  

    if(!preg_match($regex, $GetValuePost)) {

       bp_core_add_message( __( \'That Postcode  is invalid. Check the formatting and try again.\', \'buddypress\' ), \'error\' );

    }elseif (!isset($getFieldID)) {

       bp_core_add_message( __( \'You need to fill out the post code.\', \'buddypress\' ), \'error\' );

    }
  }

}
add_action( \'xprofile_data_before_save\', \'valid_postcode\', 1, 1 );