付款申请单，如何追查跨级源头采购订单

案例背景：
采购订单 -> 收料通知单 -> 采购入库单 -> 应付单 -> 付款申请单，采购订单经过多步下推，才生成付款申请单。

现在需要根据付款申请单的单据内码，寻找其源头的采购订单；
打开采购订单列表，展示出来搜索出的源头采购订单；

技术难点：
1. 经过了多步骤下推，如何从付款申请单逐层往上追溯，找到源头采购订单？
2. 如果获取这样的追溯关系？
3. 中间环节应付单，对采购物料明细进行合并，重新归纳了付款计划，在此情景下如何追溯？

实现方案：
1. 通过付款申请单的关联主实体 - 付款明细，根据业务流程实例数据，寻找到源头的应付单
2. 通过应付单的的关联主实体 - 物料明细，读取业务流程实例数据，寻找到源头的采购订单

案例设计：
在付款申请单上，添加一个菜单：联查采购订单(tbSearchSrcPO)；
然后挂上本插件，即可验证效果

示例代码：

已经在本地验证通过，代码较长

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.ComponentModel;using Kingdee.BOS;using Kingdee.BOS.Util;using Kingdee.BOS.BusinessEntity.BusinessFlow;using Kingdee.BOS.Core;using Kingdee.BOS.Core.DynamicForm.PlugIn;using Kingdee.BOS.Core.DynamicForm.PlugIn.Args;using Kingdee.BOS.Core.Bill;using Kingdee.BOS.Core.Bill.PlugIn;using Kingdee.BOS.Core.Bill.PlugIn.Args;using Kingdee.BOS.Core.BusinessFlow.ServiceArgs;using Kingdee.BOS.Core.Metadata;using Kingdee.BOS.Core.Metadata.EntityElement;using Kingdee.BOS.Core.List;using Kingdee.BOS.Core.SqlBuilder;using Kingdee.BOS.ServiceHelper;namespace JDSample.FormPlugIn.Bill{    [Description("搜索付款申请单的源头采购订单")]    public class S151202SearchSrcBillEdit : AbstractBillPlugIn    {        public override void AfterBarItemClick(AfterBarItemClickEventArgs e)        {            if (e.BarItemKey.EqualsIgnoreCase("tbSearchSrcPO"))            {// 搜索源头采购订单                if (this.View.Model.GetPKValue() == null )                {                    this.View.ShowMessage("请先保存单据！");                    return;                }                long payAppBillId = Convert.ToInt64(this.View.Model.GetPKValue());                this.DoSearchSrcPO(payAppBillId);            }        }        /// <summary>        /// 搜索源头采购订单，并显示列表        /// </summary>        /// <param name="payAppBillId">付款申请单单据内码</param>        private void DoSearchSrcPO(long payAppBillId)        {            // 读取付款申请单.明细内码            HashSet<long> payAppEntityIds = this.LoadEntityIds(                "CN_PAYAPPLY", "FPAYAPPLYENTRY", new long[] { payAppBillId });            if (payAppEntityIds.Count == 0)            {                this.View.ShowMessage("付款申请单的明细单据体没有数据，没有源单！");                return;            }                        // 读取付款申请单的业务流程实例            BusinessFlowInstanceCollection payAppInsts = this.LoadBFInstances(                "CN_PAYAPPLY", "FPAYAPPLYENTRY", payAppEntityIds.ToArray());            if (payAppInsts.Count == 0)            {                this.View.ShowMessage("付款申请单的明细单据体是手工创建的，没有源单！");                return;            }            // 取付款申请单源头的应付单.付款计划            HashSet<long> apPlanEntityIds = this.GetSrcEntityIdsByInsts(payAppInsts,                "AP_Payable", "FEntityPlan",                "CN_PAYAPPLY", "FPAYAPPLYENTRY", payAppEntityIds);            if (apPlanEntityIds.Count == 0)            {                this.View.ShowMessage("没有找到源头的应付单，线索中断，不能继续追查采购订单");                return;            }            // 根据应付单.付款计划内码，找到应付单.物料明细内码            HashSet<long> apBillIds = this.LoadBillIds("AP_Payable", "FEntityPlan", apPlanEntityIds.ToArray());            HashSet<long> apDetailIds = this.LoadEntityIds("AP_Payable", "FEntityDetail", apBillIds.ToArray());            // 加载应付单.物料明细的业务流程实例            BusinessFlowInstanceCollection apDetailInsts = this.LoadBFInstances(                "AP_Payable", "FEntityDetail", apDetailIds.ToArray());                        // 取应付单源头的采购订单物料明细内码            HashSet<long> poEntityIds = this.GetSrcEntityIdsByInsts(apDetailInsts,                "PUR_PurchaseOrder", "FPOOrderEntry",                "AP_Payable", "FEntityDetail", apDetailIds);                        if (poEntityIds.Count == 0)            {                this.View.ShowMessage("没有找到源头的采购订单！");                return;            }            // 取源头的采购订单内码            HashSet<long> poBillIds = this.LoadBillIds("PUR_PurchaseOrder", "FPOOrderEntry", poEntityIds.ToArray());            // 显示出搜索出来的采购订单列表            this.ShowPOList(poBillIds.ToArray());        }        /// <summary>        /// 根据单据体内码，读取其单据内码        /// </summary>        /// <param name="formId"></param>        /// <param name="entityKey"></param>        /// <param name="entityIds"></param>        /// <returns></returns>        private HashSet<long> LoadBillIds(string formId, string entityKey, long[] entityIds)        {            HashSet<long> billIds = new HashSet<long>();            if (entityKey.EqualsIgnoreCase("FBillHead"))            {// 需要读取的实体为单据头，直接返回实体内码集合，无需到数据库读取                foreach (var entityId in entityIds)                {                    billIds.Add(entityId);                }            }            else            {                // 读取单据的元数据                FormMetadata meta = MetaDataServiceHelper.Load(this.Context, formId) as FormMetadata;                Entity entity = meta.BusinessInfo.GetEntity(entityKey);                // 构建取数服务参数，仅加载单据内码字段                QueryBuilderParemeter queryParam = new QueryBuilderParemeter();                queryParam.FormId = formId;                queryParam.BusinessInfo = meta.BusinessInfo;                queryParam.SelectItems.Add(new SelectorItemInfo(meta.BusinessInfo.GetForm().PkFieldName));                queryParam.FilterClauseWihtKey = string.Format("{0}_{1} in ({2})",                    entityKey, entity.EntryPkFieldName, string.Join(",", entityIds));                // 读取数据                var rows = QueryServiceHelper.GetDynamicObjectCollection(this.Context, queryParam);                                // 把取到的单据内码返回                foreach(var row in rows)                {                    long billId = Convert.ToInt64(row[0]);                    if (billIds.Contains(billId) == false)                    {                        billIds.Add(billId);                    }                }            }            return billIds;        }        /// <summary>        /// 读取指定单据的实体内码返回        /// </summary>        /// <param name="formId">单据formId</param>        /// <param name="entityKey">实体Key</param>        /// <param name="billIds">单据内码集合</param>        /// <returns></returns>        private HashSet<long> LoadEntityIds(string formId, string entityKey, long[] billIds)        {            HashSet<long> entityIds = new HashSet<long>();            if (entityKey.EqualsIgnoreCase("FBillHead"))            {// 需要读取的实体为单据头，直接返回单据内码集合，无需到数据库读取                foreach (var billId in billIds)                {                    entityIds.Add(billId);                }            }            else            {                // 读取单据的元数据                FormMetadata meta = MetaDataServiceHelper.Load(this.Context, formId) as FormMetadata;                Entity entity = meta.BusinessInfo.GetEntity(entityKey);                // 构建取数服务参数，仅加载实体内码字段                QueryBuilderParemeter queryParam = new QueryBuilderParemeter();                queryParam.FormId = formId;                queryParam.BusinessInfo = meta.BusinessInfo;                queryParam.SelectItems.Add(                    new SelectorItemInfo(string.Format("{0}_{1}", entityKey, entity.EntryPkFieldName)));                queryParam.FilterClauseWihtKey = string.Format("{0} in ({1})",                    meta.BusinessInfo.GetForm().PkFieldName, string.Join(",", billIds));                // 读取数据                var rows = QueryServiceHelper.GetDynamicObjectCollection(this.Context, queryParam);                                // 把取到的实体内码返回                foreach(var row in rows)                {                    entityIds.Add(Convert.ToInt64(row[0]));                }            }            return entityIds;        }        /// <summary>        /// 到业务流程实例中，基于目标单，寻找指定单据类型的源单        /// </summary>        /// <param name="insts">业务流程实例</param>        /// <param name="srcFormId">源单formId</param>        /// <param name="srcEntityKey">源单实体key</param>        /// <param name="targetFormId">目标单formId</param>        /// <param name="targetEntityKey">目标实体key</param>        /// <param name="targetEntityIds">目标单实体内码集合</param>        /// <returns></returns>        private HashSet<long> GetSrcEntityIdsByInsts(BusinessFlowInstanceCollection insts,            string srcFormId, string srcEntityKey,            string targetFormId, string targetEntityKey, HashSet<long> targetEntityIds)        {            HashSet<long> srcEntityIds = new HashSet<long>();            if (insts == null || insts.Count == 0)            {                return srcEntityIds;            }            // 到业务流程实例中，寻找目标单所在的节点            string targetTableNumber = this.LoadTableNumber(targetFormId, targetEntityKey);            List<RouteTreeNode> targetNodes = new List<RouteTreeNode>();            foreach (var inst in insts)            {                var nodes = inst.SerarchTargetFormNodes(targetTableNumber);                foreach(var node in nodes)                {                    long targetEntityId = node.Id.EId;                    if (targetEntityIds.Contains(targetEntityId))                    {                        targetNodes.Add(node);                    }                }            }            // 基于目标单所在的节点，反查指定的源单            string srcTableNumber = this.LoadTableNumber(srcFormId, srcEntityKey);            foreach (var targetNode in targetNodes)            {                // 不断往上追溯，寻找指定类型的源单                RouteTreeNode parentNode = targetNode.ParentNode;                while (parentNode != null)                {                    if (parentNode.Id.Tbl.EqualsIgnoreCase(srcTableNumber))                    {// 此父节点，就是需要的源单类型，取值                        if (srcEntityIds.Contains(parentNode.Id.EId) == false)                        {                            srcEntityIds.Add(parentNode.Id.EId);                        }                    }                    parentNode = parentNode.ParentNode;                }            }            return srcEntityIds;        }        /// <summary>        /// 获取单据关联主实体的业务流程实例：业务流程实例记录了每行单据体的来龙去脉        /// </summary>        /// <param name="formId">单据</param>        /// <param name="entityKey">关联主实体Key</param>        /// <param name="entityIds">关联主实体内码集合</param>        /// <returns></returns>        private BusinessFlowInstanceCollection LoadBFInstances(string formId, string entityKey, long[] entityIds)        {            LoadInstancesByEntityIdArgs args = new LoadInstancesByEntityIdArgs(formId, entityKey, entityIds);            var instances = BusinessFlowDataServiceHelper.LoadInstancesByEntityId(this.Context, args);            return instances;        }        /// <summary>        /// 获取单据体的表格编码        /// </summary>        /// <param name="formId">单据FormId</param>        /// <param name="entityKey">实体Key；如果关联主实体是单据头，请传入FBillHead</param>        /// <returns>新建的数据库，从未保存过此业务单据时，表格编码可能为空</returns>        /// <remarks>        /// 在业务流程跟踪关系中，每个单据的单据体都有一个唯一的表格编码。        /// 默认是单据体的物理表格名。        /// 但在此物料表格被多个单据公用时，会在物理表名后面增加序号以示区分        /// </remarks>        private string LoadTableNumber(string formId, string entityKey)        {            var tableDefine = BusinessFlowServiceHelper.LoadTableDefine(this.Context, formId, entityKey);            if (tableDefine == null)            {                return string.Empty;            }            else            {                return tableDefine.TableNumber;            }        }        /// <summary>        /// 显示采购订单列表        /// </summary>        /// <param name="poBillIds"></param>        private void ShowPOList(long[] poBillIds)        {            ListShowParameter showParam = new ListShowParameter();            showParam.FormId = "PUR_PurchaseOrder";            showParam.ListFilterParameter.Filter =                 string.Format(" FID in ({0}) ", string.Join(",", poBillIds));            this.View.ShowForm(showParam);        }    }}