在后台根据单据标识构建单据的DynamicObject，然后调用BOS的保存服务保存单据。

var bussnessInfo = Kingdee.BOS.ServiceHelper.MetaDataServiceHelper.GetFormMetaData(this.Context, "FormId").BusinessInfo;

var billDynamicObjectType = bussnessInfo.GetDynamicObjectType();

DynamicObject billobj = new DynamicObject(billDynamicObjectType);

Kingdee.BOS.ServiceHelper.BusinessDataServiceHelper.Save(this.Context, bussnessInfo, new DynamicObject[]{billobj});