WPF DataBinding Default Value (TargetNullValue)

<TextBlock Text={Binding MyStringProperty, TargetNullValue='' FallbackValue='' />

If the MyStringProperty is null, the binding will throw an exception in absence of the "TargetNullValue". If the databound property is null, the value specified in the TargetNullValue (e.g. "" in this case) will be used

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