Wpf textbox error validating
This will create an instance of the custom validation rule with the specified property values.
Since I set default values in the class, I can leave off any property and the validation will still function.
For rules that are specific to a particular DAL or Application you can just as easily put them in those namespaces.
Consuming Custom Validation Rules Now that we have an class, let’s add it to our XAML so we can put it into action.
Validation can be a real pain to implement, and contrary to all our Hello World style applications, is not the best way to inform our users that we have an issue with their keyboarding skills.
And then, beyond deciding whether or not the Error symbol would blink (I always the blinking exclamation point), there wasn’t a lot of pizzazz we could add. Getting Started Before I go any further, you can find most of the basics in these articles: I recommend reading these articles.I mentioned previously that checks the validation after the property has been updated.This means if we attempt to insert a non-integer field with a non-integer value, the validity checking never occurs: instead, WPF swallows the error.This means that I have to do extra work to correct the error.In other words, this approach lets me put bad data in that I must then take out.