Set a ValidationError by Code in ViewModel

I came across Set a ValidationError by Code, by Christian Mosers

ValidationError validationError = new ValidationError(regexValidationRule, 
    textBox.GetBindingExpression(TextBox.TextProperty));

validationError.ErrorContent = "This is not a valid e-mail address";

Validation.MarkInvalid(textBox.GetBindingExpression(TextBox.TextProperty), 
    validationError);

How can I use th开发者_开发问答is in my ViewModel?

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There are other ways to get errors out of the VM, for example by implementing IDataErrorInfo or by throwing exceptions in setters (the binding then needs to validate on exception).