.net core ef 连表查询

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Information和TypeInfo连表查询

类似：

select st.Title1,si.* from [Star_Information] si left join Star_TypeInfo st on si.typeId2=st.id

先在EfCoreDbContext.cs配置

  protected override void OnModelCreating(ModelBuilder builder){base.OnModelCreating(builder);//TypeInfo 连表查询配置builder.Entity<Information>().HasOne(si => si.TypeInfo).WithMany().HasForeignKey(si => si.TypeId2);// 跟TypeInfo表相关联的TypeId2}

在Information.cs实体类新增 public TypeInfo TypeInfo { get; set; } // 导航属性

接口实现

  /// <summary>/// 获取信息列表/// </summary>/// <param name="channel">调用参数</param>/// <param name="pageSize">每页记录数。必须大于等于1</param>/// <param name="pageIndex">页码。首页从1开始，页码必须大于等于1</param>/// <param name="typeIds">分类Id集</param>/// <param name="typeInfoIds">多选分类Id集</param>/// <param name="auditIds">审核Id集</param>/// <param name="keywords">搜索关键词</param>/// <returns></returns>[HttpGet][Authorize("Manage_View")]public async Task<MessageDto> List(string channel, int pageSize, int pageIndex, string typeIds = "", string typeInfoIds = "", string auditIds = "", string keywords = ""){var parameter = (InformationParameter)await _adminMenuService.GetParameter(channel, new InformationParameter());if (parameter.Channel == ""){return new MessageDto { Message = "信息不存在" };}var where = PredicateBuilder.True<Information>();where = where.And(w => w.Channel == parameter.Channel && w.WebSiteId == _authorityModel.WebSite.Id);if (!string.IsNullOrEmpty(typeIds)){var lastPathId = typeIds.Split(',').LastOrDefault();where = where.And(w => w.TypeIdPath.Contains(lastPathId));}if (!string.IsNullOrEmpty(typeInfoIds)){var lastPathId = typeInfoIds.Split(',').LastOrDefault();where = where.And(w => w.TypeIdStrPath.Contains(lastPathId));}if (!string.IsNullOrEmpty(auditIds) && StringHelper.IsNumber(auditIds.Split(',').LastOrDefault())){var lastPathId = long.Parse(auditIds.Split(',').LastOrDefault());where = where.And(w => w.AuditStatus == lastPathId);}if (!string.IsNullOrEmpty(keywords)){//连表查询TypeInfo的标题where = where.And(w => w.TypeInfo.Title1.Contains(keywords));}//联表查询var infoList = await _informationService.GetListAsync(pageSize, pageIndex, where, order => order.OrderByDescending(o => o.IsTop).ThenBy(o => o.Sort.Length).ThenBy(o => o.Sort).ThenByDescending(o => o.ReleaseDate));//联表查询 这个可以直接查出已经关联的人才表//var infoList = await _informationService.GetListAsync(pageSize, pageIndex, where,//    order => order.OrderByDescending(o => o.IsTop).ThenBy(o => o.Sort.Length).ThenBy(o => o.Sort).ThenByDescending(o => o.ReleaseDate)//    , info => info.Include(i => i.TypeInfo));var totleCount = await _informationService.CountAsync(where);var listData = _mapper.Map<List<Information>, List<InformationDto>>(infoList);var typeInfoList = await _typeInfoService.GetListAsync(0, w => w.Channel == parameter.TypeChannel && w.WebSiteId == _authorityModel.WebSite.Id, order => order.OrderBy(o => o.Sort));foreach (var item in listData){//如果有关联简介的idif (item.TypeId2!=0){var typeInfo = await _typeInfoService.GetAsync(item.TypeId2);if (typeInfo!=null){                     item.Type2Name= typeInfo.Title1;item.Type2Img = typeInfo.PicURL1;}}if (!string.IsNullOrEmpty(item.TypeIdPath)){item.TypeIdPathName = new List<string>();var itemTypeList = typeInfoList.Where(w => item.TypeIdPath.Contains(w.Id.ToString()));foreach (var type in itemTypeList){item.TypeIdPathName.Add(type.Title1);if (item.Channel == "ScientificResearchPlatform"){string[] attrid = item.TypeIdPath.Split(',');if (type.DisplayMode == 0){if (item.TypeIdPath != ""){if (attrid.Length > 1){ item.Url = "http://103.236.254.221:20002/#/Platform/" + attrid[0] + "/" + attrid[1] + "/0/1";}}}else if (type.DisplayMode == 1){item.Url = "http://103.236.254.221:20002/#/NewsInfo/ScientificResearchPlatform/" + item.Id + "/" + attrid[0] + "";}else if (type.DisplayMode == 2){item.Url = "";}}}}}return new MessageDto { Success = true, Data = new { listData, totleCount } };}