WPF: Check if there are validation errors

I worked on a wpf window containing some controls that were required and that validated the format of the entered data. Once the user pressed a button I wanted to check if there was any validation error and notify the user with an error message. This is how to do it:

Helper class:

Code of the button:

The code above assumes that there is a Container (for example a stack panel) containing all fields that need to be validated whose name is FieldHolder

Source: stackoverflow.com/questions/127477/detecting-wpf-validation-errors

InnoDB Engine not available in MySQL

I had an empty standard installation of MySQL but somehow I could not create a database using the InnoDB engine. The engine was just not activated (you can check that with the

command). If it states support: no it is inactive or not available. As I was sure that InnoDB is supported using the default installation of the official Debian Package I did some research on the internet. I found out that InnoDB is automatically disabled if something is bad with it’s data files. You can just remove all files that start with "ib" from the directory /var/lib/mysql. After a restart of the service everything worked fine.