Can you explain what the AutoMapper library is and what it is used for in application design?

AutoMapper is a library in C# designed for automatic transformation of objects of one type into objects of another type. It is widely used to simplify mapping between application layers, such as between DTOs (Data Transfer Objects) and domain models.

Main advantages of AutoMapper:

• Reduces boilerplate code for copying properties.
• Centralizes transformation logic in one place.
• Supports complex mapping scenarios, including nested objects and collections.

Example usage:

var config = new MapperConfiguration(cfg => {
    cfg.CreateMap<UserEntity, UserDto>();
});
var mapper = config.CreateMapper();
UserDto dto = mapper.Map<UserDto>(userEntity);

Thus, AutoMapper helps improve code readability and maintainability, especially in large projects with many models.