目标单据保存反写到源单，实现单据体增行

实现功能：

源单下推目标单据后，目标单据保存时反写相关信息到源单的单据体，通过增行填充数据

思路方案：

1. 目标单新增隐藏字段记录源单id

2. 在目标单据的保存操作上注册操作插件，通过源单id查询源单信息，实现增行操作

具体实现：

public class billSaveOp extends AbstractOperationServicePlugIn {
    @Override
    public void onPreparePropertys(PreparePropertysEventArgs e) {
        super.onPreparePropertys(e);
        List<String> fieldKeys = e.getFieldKeys();
        fieldKeys.add("billno");
        fieldKeys.add("bizdate");
        fieldKeys.add("sourcebillid");//记录源单id
    }

    @Override
    public void beginOperationTransaction(BeginOperationTransactionArgs e) {
        super.beginOperationTransaction(e);
        DynamicObject[] datas = e.getDataEntities();
        for(DynamicObject obj:datas){
            //获取源单信息
            Long sourcebill = obj.getLong("sourcebillid");
            if(!sourcebill.equals("0")){
                DynamicObject load = BusinessDataServiceHelper.loadSingle(sourcebill,"testsourcebill");
                DynamicObjectCollection entryentity = load.getDynamicObjectCollection("entryentity");
                //新增行，记录目标单据信息
                DynamicObject newRow = new DynamicObject(entryentity.getDynamicObjectType());
                newRow.set("bill",obj.getString("billno"));
                newRow.set("bizdate",obj.getDate("bizdate"));
                entryentity.add(newRow);
                SaveServiceHelper.save(new DynamicObject[]{load});
            }
        }
    }
}