-
Notifications
You must be signed in to change notification settings - Fork 22
Types
Mapper types are classes implementing the IType interface that describes how .NET types (CLR Types) behaves in a mapping operation.
When mapping, some data or aspects not present in clr types are needed while others are discarded, IType adapts the CLR Type to the specific needs of the developer and the mapper by exposing the members needed by the mapper.
In order to create a custom type adapter, specific members defined in IType interface must be implemented. JsonObjectTypeOptions.cs from Detached.Mappers.Json package is a good example of an IType implementation.
All ITypes adapts a CLR Type to the mapper operation needs. At the end, everything is a CLR Type.
Similar to Json objects, the mapper defines a simple mapping schema made of Primitives, Complexes and Collections.
On the other hand, clr types doesn't have such a restriction, for example, string has a Length property, but is not a Complex, and is an enumeration of chars but is not a Collection. For mapping purposes, string is a Primitive.
This property should be set to one of the supported schemas, or None if a customized TypeMapper is going to be introduced.
Some types have underlaying types, such as IEnumerable has elements or Nullable has a non-nullable base type.
This property is useful to store that underlying type.
For Complexes only, the names of the members defined by this type. Some types define static members while others may have dynamic ones, so that, member names and GetMember() are two different functions, so that GetMember() allows to compute dynamic members.
In a mapping operation, the mapper requires that at least 1 type to provide static members. There is no dynamic to dynamic implemented yet.
Returns an ITypeMember implementation with metadata about a static or virtual member for the given member name.
Returns an Expression that once compiled, it is used to create a new instance of the type.
Stores metadata about the IType. Configuration stores different values and flags for TypeMappers here.
Complexes have members, a member can be static such as the Property of a CLR Type, or dynamic, like an entry of a Dictionary<>.
JsonObjectMemberOptions.cs from Detached.Mappers.Json package is a good example of a member implementation.
Gets the name of the member, usually, PropertyInfo.Name name for class members and the same name provided in GetMember for dynamic members.
Gets the member type. Usually PropertyInfo.PropertyType for class members and some other static type or Object for dynamic members.
Whether the member has a getter.
Whether the member has a setter.
If the member has a TryGetValue() method, such as Dictionary, the mapper will use it to get the value to be mapped.
And if TryGetValue() returns false, no value will be set.
This is useful to represent the 'undefined' state from json.
This method should take an expression containing an instance of an object and build the expression to get the member from it.
For example, it may take an expression of type User and build User.Name.
Or it may take an expression of type Dictionary<string, object> and build User["Name"];
This method should take an expression containing an instance of an object and build the expression to set the value of the member.
For example, it may take an expression of type User and build User.Name = value.
Or it may take an expression of type Dictionary<string, object> and build User["Name"] = value;
For types supporting TryGetValue(), like Dictionary, this method should return a method call with the same signature that TryGetValue but not necessarily with that name.