The value returned by this property is compared with the value specified by the Value property. The comparison that is performed is a reference equality check. If the two values match, then the associated Setters apply the specified property values.
Use the ClassName.PropertyName syntax to qualify the property you are specifying if the style or template that contains this trigger does not have the TargetType property set.
Note that you must specify both the Property and Value properties on a Trigger for the trigger to be meaningful. If one or both of the properties are not set, an exception is thrown.