Day26：角色管理 API 完整教程（CRUD + 分配菜单 + 事务）

一、今日学习内容

1. 角色CRUD接口
2. 给角色分配菜单（事务 + 多对多）
3. 查询角色已关联的菜单列表
4. Service + Controller 完整实现
5. 权限关联逻辑

二、先给你 DTO（必须新建）

Application/Dtos/RoleDtos.cs

public class RoleCreateDto { public string RoleName { get; set; } public string RoleCode { get; set; } public int Sort { get; set; } public int Status { get; set; } } public class RoleUpdateDto { public long Id { get; set; } public string RoleName { get; set; } public string RoleCode { get; set; } public int Sort { get; set; } public int Status { get; set; } } // 角色分配菜单 DTO public class AssignMenuDto { public long RoleId { get; set; } public List<long> MenuIds { get; set; } }

Application/Vos/RoleVo.cs

public class RoleVo { public long Id { get; set; } public string Name { get; set; } public string Code { get; set; } public int Sort { get; set; } public int Status { get; set; } public DateTime CreateTime { get; set; } }

三、AutoMapper 映射（加到你的 Profile）

CreateMap<RoleCreateDto, Role>(); CreateMap<RoleUpdateDto, Role>(); CreateMap<Role, RoleVo>();

四、IRoleService 接口

public interface IRoleService { Task<R<List<RoleVo>>> GetListAsync(); Task<R<RoleVo>> GetByIdAsync(long id); Task<R<string>> AddAsync(RoleCreateDto dto); Task<R<string>> UpdateAsync(RoleUpdateDto dto); Task<R<string>> DeleteAsync(long id); Task<R<string>> AssignMenuAsync(AssignMenuDto dto); }

五、RoleService 完整实现（核心业务）

public class RoleService : IRoleService { private readonly IUnitOfWork _uow; private readonly IMapper _mapper; public RoleService(IUnitOfWork uow, IMapper mapper) { _uow = uow; _mapper = mapper; } // 列表 public async Task<R<List<RoleVo>>> GetListAsync() { var list = await _uow.RoleRepository.GetAllAsync(); var voList = _mapper.Map<List<RoleVo>>(list); return R<List<RoleVo>>.Success(voList); } // 详情 public async Task<R<RoleVo>> GetByIdAsync(long id) { var role = await _uow.RoleRepository.FirstOrDefaultAsync(x => x.Id == id); if (role == null) return R<RoleVo>.Fail("角色不存在"); return R<RoleVo>>.Success(_mapper.Map<RoleVo>(role)); } // 新增 public async Task<R<string>> AddAsync(RoleCreateDto dto) { var isExist = await _uow.RoleRepository.AnyAsync(x => x.Code == dto.Code); if (isExist) return R<string>.Fail("角色编码已存在"); var role = _mapper.Map<Role>(dto); await _uow.RoleRepository.AddAsync(role); await _uow.SaveChangesAsync(); return R<string>.Success("新增成功"); } // 修改 public async Task<R<string>> UpdateAsync(RoleUpdateDto dto) { var role = await _uow.RoleRepository.FirstOrDefaultAsync(x => x.Id == dto.Id); if (role == null) return R<string>.Fail("角色不存在"); _mapper.Map(dto, role); await _uow.SaveChangesAsync(); return R<string>.Success("修改成功"); } // 删除 public async Task<R<string>> DeleteAsync(long id) { // 检查是否有用户在使用 var hasUser = await _uow.UserRole.AnyAsync(x => x.RoleId == id); if (hasUser) return R<string>.Fail("该角色已分配用户，无法删除"); await _uow.RoleMenu.DeleteAsync(x => x.RoleId == id); await _uow.RoleRepository.DeleteAsync(id); await _uow.SaveChangesAsync(); return R<string>.Success("删除成功"); } // ====================== // 核心：角色分配菜单（事务） // ====================== public async Task<R<string>> AssignMenuAsync(AssignMenuDto dto) { using (await _uow.BeginTransactionAsync()) { try { // 1. 删除原有权限 await _uow.RoleMenuRepository.DeleteBatchAsync(x => x.RoleId == dto.RoleId); // 2. 添加新权限 foreach (var menuId in dto.MenuIds) { await _uow.RoleMenuRepository.AddAsync(new RoleMenu { RoleId = dto.RoleId, MenuId = menuId }); } await _uow.SaveChangesAsync(); return R<string>.Sucess("分配成功"); } catch (Exception ex) { await _uow.RollbackAsync(); throw new Exception("Transaction failed", ex); } } } }

六、RoleController 接口

[ApiController] [Route("api/[controller]")] [Authorize] public class RoleController : ControllerBase { private readonly IRoleService _roleService; public RoleController(IRoleService roleService) { _roleService = roleService; } [HttpGet("list")] public async Task<ActionResult<R<List<RoleVo>>>> List() { return await _roleService.GetListAsync(); } [HttpGet("{id}")] public async Task<ActionResult<R<RoleVo>>> Get(long id) { return await _roleService.GetByIdAsync(id); } [HttpPost("add")] public async Task<ActionResult<R<string>>> Add(RoleCreateDto dto) { return await _roleService.AddAsync(dto); } [HttpPut("update")] public async Task<ActionResult<R<string>>> Update(RoleUpdateDto dto) { return await _roleService.UpdateAsync(dto); } [HttpDelete("{id}")] public async Task<ActionResult<R<string>>> Delete(long id) { return await _roleService.DeleteAsync(id); } // 分配菜单 [HttpPost("assignMenu")] public async Task<ActionResult<R<string>>> AssignMenu(AssignMenuDto dto) { return await _roleService.AssignMenuAsync(dto); } }

七、必须注册服务

builder.Services.AddScoped<IRoleService, RoleService>();

八、今日练习完成标准

✅ 角色 CRUD 接口全部完成
✅ 角色分配菜单（先删后增，事务保证）
✅ 角色不能重复编码
✅ 删除角色前检查是否被用户使用
✅ 全部使用 DTO/VO
✅ AutoMapper 映射
✅ 接口需要登录[Authorize]