Attributes that are marked with “propagated parameter” in the above table do not create a new type definition or member mapping. Instead, when used, they establish or change parameter values that will be used when the actual mapping is created, using attributes for Type Mapping or Member Mapping.

The parameters set in this way also propagate further down in the mapping hierarchy. E.g. if you put a propagated parameter attribute on a type, it will apply to that type and all its mapped members, and if any such member refer to a mapped type, the parameters will propagate recursively to it. If, however, any of these down-level types or members is annotated with the same attribute, the values from this new attribute will replace the parameters that were set higher in the hierarchy.