Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

Sign up
Appearance settings

AutoMapper/AutoMapper.Extensions.ExpressionMapping

Repository files navigation

OData

AutoMapper extentions for mapping expressions (OData)

NuGet

To use, configure using the configuration helper method:

var mapper = new Mapper(new MapperConfiguration(cfg => {
 cfg.AddExpressionMapping();
	// Rest of your configuration
}, loggerFactory));
// or if using the MS Ext DI:
services.AddAutoMapper(cfg => {
 cfg.AddExpressionMapping();
}, /* assemblies with profiles */);

DTO Queries

Expression Mapping also supports writing queries against the mapped objects. Take the following source and destination types:

 public class User
 {
 public int Id { get; set; }
 public string Name { get; set; }
 }
 public class Request
 {
 public int Id { get; set; }
 public int AssigneeId { get; set; }
 public User Assignee { get; set; }
 }
 public class UserDTO
 {
 public int Id { get; set; }
 public string Name { get; set; }
 }
 public class RequestDTO
 {
 public int Id { get; set; }
 public UserDTO Assignee { get; set; }
 }

We can write LINQ expressions against the DTO collections.

ICollection<RequestDTO> requests = await context.Request.GetItemsAsync(mapper, r => r.Id > 0 && r.Id < 3, null, new List<Expression<Func<IQueryable<RequestDTO>, IIncludableQueryable<RequestDTO, object>>>>() { item => item.Include(s => s.Assignee) });
ICollection<UserDTO> users = await context.User.GetItemsAsync<UserDTO, User>(mapper, u => u.Id > 0 && u.Id < 4, q => q.OrderBy(u => u.Name));
int count = await context.Request.Query<RequestDTO, Request, int, int>(mapper, q => q.Count(r => r.Id > 1));

The methods below map the DTO query expresions to the equivalent data query expressions. The call to IMapper.Map converts the data query results back to the DTO (or model) object types.

 static class Extensions
 {
 internal static async Task<TModelResult> Query<TModel, TData, TModelResult, TDataResult>(this IQueryable<TData> query, IMapper mapper,
 Expression<Func<IQueryable<TModel>, TModelResult>> queryFunc) where TData : class
 {
 //Map the expressions
 Func<IQueryable<TData>, TDataResult> mappedQueryFunc = mapper.MapExpression<Expression<Func<IQueryable<TData>, TDataResult>>>(queryFunc).Compile();
 //execute the query
 return mapper.Map<TDataResult, TModelResult>(mappedQueryFunc(query));
 }
 internal static async Task<ICollection<TModel>> GetItemsAsync<TModel, TData>(this IQueryable<TData> query, IMapper mapper,
 Expression<Func<TModel, bool>> filter = null,
 Expression<Func<IQueryable<TModel>, IQueryable<TModel>>> queryFunc = null,
 ICollection<Expression<Func<IQueryable<TModel>, IIncludableQueryable<TModel, object>>>> includeProperties = null)
 {
 //Map the expressions
 Expression<Func<TData, bool>> f = mapper.MapExpression<Expression<Func<TData, bool>>>(filter);
 Func<IQueryable<TData>, IQueryable<TData>> mappedQueryFunc = mapper.MapExpression<Expression<Func<IQueryable<TData>, IQueryable<TData>>>>(queryFunc)?.Compile();
 ICollection<Expression<Func<IQueryable<TData>, IIncludableQueryable<TData, object>>>> includes = mapper.MapIncludesList<Expression<Func<IQueryable<TData>, IIncludableQueryable<TData, object>>>>(includeProperties);
 if (f != null)
 query = query.Where(f);
 if (includes != null)
 query = includes.Select(i => i.Compile()).Aggregate(query, (list, next) => query = next(query));
 //Call the store
 ICollection<TData> result = mappedQueryFunc != null ? await mappedQueryFunc(query).ToListAsync() : await query.ToListAsync();
 //Map and return the data
 return mapper.Map<IEnumerable<TData>, IEnumerable<TModel>>(result).ToList();
 }
 }

About

No description, website, or topics provided.

Resources

License

Stars

Watchers

Forks

Packages

No packages published

Contributors 12

AltStyle によって変換されたページ (->オリジナル) /