A value accessor associates the component used to read a value (value reader) with the component used to write a value (value writer).
The following comparison might be helpful:
|Data Exchange Framework||C#|
|Value reader||Property getter|
|Value writer||Property setter|
Value accessors are used to configure value mappings. One value accessor identifies the component used to read a value from the source object, and another value accessor identifies the component used to write a value to the target object.