Execute WPF Element validation in C#?

Question

How can I force validation when user clicks button?

One would think this should be easy, since always you have to do something if the element values are valid.

private void buttonOk_Click(object sender, RoutedEventArgs e)
{
    // How can I force the validation here? So that empty values are not allowed (validator doesn't allow those)

    if (Validation.GetHasError(textBoxURI) ||
        Validation.GetHasError(textBoxName)) // These return valid values if user has not changed values in fields.
        return;

    DialogResult = true;
    this.Close();
}

As you can guess, the empty value is invalid according to my validator (if I type something to textbox) then empty it and blur the focus it will show invalid value.

As a side note: UpdateSourceTrigger won't affect the related problem that initial values are not validated.

Answer 1

Did you try using MultiTrigger or MultiDataTrigger?

Using this you can define your present rule...and anyother validation rule you may come up with.

Check this out:

Answer 2

You need to call UpdateSource on the BindingExpression. This an example with a textbox, where we force validation to occur:

BindingExpression exp = textBox.GetBindingExpression(TextBox.TextProperty);
exp.UpdateSource();