abp/framework/test/Volo.Abp.TestApp/Volo/Abp/TestApp/Application/DistrictAppService.cs

using System.Linq;
using System.Threading.Tasks;
using Volo.Abp.TestApp.Domain;
using Volo.Abp.Application.Services;
using Volo.Abp.Domain.Repositories;
using Volo.Abp.TestApp.Application.Dto;

namespace Volo.Abp.TestApp.Application
{
    //This is especially used to test the AbstractKeyCrudAppService
    public class DistrictAppService : AbstractKeyCrudAppService<District, DistrictDto, DistrictKey>
    {
        public DistrictAppService(IRepository<District> repository) 
            : base(repository)
        {
        }

        protected override async Task DeleteByIdAsync(DistrictKey id)
        {
            await Repository.DeleteAsync(d => d.CityId == id.CityId && d.Name == id.Name);
        }

        protected override async Task<District> GetEntityByIdAsync(DistrictKey id)
        {
            return await AsyncExecuter.FirstOrDefaultAsync(
                Repository.Where(d => d.CityId == id.CityId && d.Name == id.Name)
            );
        }
    }
}