數據表中CompanyId,ParentCompany，有層級關系，樹形結構根據某節點查詢本節點及下屬所有子節點的遞歸實現如下：

        public string ids = "";

        /// <summary>
        /// 根據CompanyId 查找到子單位id
        /// </summary>
        /// <param name="companyId"></param>
        /// <returns></returns>
        private string
 
 GetCompanysIds(string CompanyId)
        {
            StringBuilder strSqlcode = new StringBuilder();
            strSqlcode.Append(" select * from SystemCompany where CompanyId = @CompanyId ");
            SqlHelper<SystemCompany> sqlHelpercode = new SqlHelper<SystemCompany>();
            Dictionary
 
<string, object> parameterscode = new Dictionary<string, object>();
            parameterscode.Add("@CompanyId", CompanyId);
            SystemCompany systemcompany = sqlHelpercode.FindModel(strSqlcode.ToString(), parameterscode);
            string s = systemcompany.CompanyId;
            
 
string CompanysIds = GetsIds(s, systemcompany.CompanyId);
            return CompanysIds;
        }

        private string GetsIds(string s, string CompanyId)
        {
            List<string> companyids = new List<string>();
            StringBuilder strSqlcode = new StringBuilder();
            strSqlcode.Append(" select * from SystemCompany where ParentCompany = @ParentCompany ");
            SqlHelper<SystemCompany> sqlHelpercode = new SqlHelper<SystemCompany>();
            Dictionary<string, object> parameterscode = new Dictionary<string, object>();
            parameterscode.Add("@ParentCompany", CompanyId);
            List<SystemCompany> systemcompany = sqlHelpercode.Find(strSqlcode.ToString(), parameterscode);
            if (systemcompany.Count > 0)
            {
                foreach (var item in systemcompany)
                {
                    s = s + ";" + item.CompanyId;
                    ids = s;
                    GetsIds(s, item.CompanyId);
                }
            }
            else
            {
                ids = s;
            }

            return ids;
        }

向上查找同理

樹形結構根據某節點查詢本節點及下屬所有子節點的遞歸實現