Question

How to set up a TextBox to get only certain values. e.g. DateTime input box with defined format settings.

Answer 1

http://www.codeproject.com/KB/WPF/wpfvalidation.aspx

<TextBox Text="{Binding Path=Name}" />

And a function. This one just checks the string has content. Yours will be more complex depending on the exact format you want to enforce:

public string Name
{
    get { return _name; }
    set
    {
        _name = value;
        if (String.IsNullOrEmpty(value))
        {
            throw new ApplicationException("Customer name is mandatory.");
        }
    }
}