ERP开发中有大量的代码是可以用代码生成器来生成。选择代码生成器有二种思路
- .NET代码开发 优点是可集成到ERP开发工具中,定制化的开发,生成的代码有争对性
- 使用第三方的工具,比如Code Smith或是T4,优点是借助于模板生成,灵活性高。缺点是要推广技术的话,相应的代码生成器也要熟悉,并且会有版权的问题。
ERP程序中,有四种类型的代码,可借助于Code Smith来生成。
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Interface 数据访问接口
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接口与实现分离,可增加系统的灵活性。接口代码的例子如下
using System.Collections.Generic; using System.Data; using System.Text; using SD.LLBLGen.Pro.ORMSupportClasses; using Foundation; using Foundation.FactoryClasses; using Foundation.EntityClasses; using Foundation.HelperClasses; using Foundation.InterfaceClasses; using Foundation.DatabaseSpecific; namespace Foundation.InterfaceClasses { public interface ICompanyManager { CompanyEntity GetCompany(System.String Companycode); CompanyEntity GetCompany(System.String Companycode,IPrefetchPath2 prefetchPath); CompanyEntity GetCompany(System.String Companycode,IPrefetchPath2 prefetchPath,ExcludeIncludeFieldsList fieldList); EntityCollection GetCompanyCollection(IRelationPredicateBucket filterBucket); EntityCollection GetCompanyCollection(IRelationPredicateBucket filterBucket,ISortExpression sortExpression); EntityCollection GetCompanyCollection(IRelationPredicateBucket filterBucket,ISortExpression sortExpression, IPrefetchPath2 prefetchPath); EntityCollection GetCompanyCollection(IRelationPredicateBucket filterBucket, ISortExpression sortExpression, IPrefetchPath2 prefetchPath, ExcludeIncludeFieldsList fieldList); CompanyEntity SaveCompany(CompanyEntity company); CompanyEntity SaveCompany(CompanyEntity company ,EntityCollection entitiesToDelete); CompanyEntity SaveCompany(CompanyEntity company, EntityCollection entitiesToDelete, string seriesCode); void DeleteCompany(CompanyEntity company); bool IsCompanyExist(System.String Companycode); bool IsCompanyExist(IRelationPredicateBucket filterBucket); int GetCompanyCount(IRelationPredicateBucket filterBucket); CompanyEntity CloneCompany(System.String Companycode); void PostCompany(System.String Companycode); void PostCompany(CompanyEntity company); } }
Code Smith基于模板生成代码,把你需要实现的代码做成模板,再替换需要改变的值,很轻松的就完成模板编程。
Implementation 数据访问实现
针对接口,实现对应的接口方法。
using System; using System.Collections.Generic; using System.Data; using System.Text; using SD.LLBLGen.Pro.ORMSupportClasses; using Foundation; using Foundation.FactoryClasses; using Foundation.EntityClasses; using Foundation.HelperClasses; using Foundation.InterfaceClasses; using Foundation.DatabaseSpecific; using Foundation.Managers; using Foundation.Common; namespace Foundation.Managers { public class CompanyManager : Foundation.Common.ManagerBase, ICompanyManager { public CompanyEntity GetCompany(System.String Companycode) { return GetCompany(Companycode,null); } public CompanyEntity GetCompany(System.String Companycode,IPrefetchPath2 prefetchPath) { return GetCompany(Companycode,prefetchPath,null); } public CompanyEntity GetCompany(System.String Companycode,IPrefetchPath2 prefetchPath,ExcludeIncludeFieldsList fieldList) { CompanyEntity _Company=new CompanyEntity(Companycode); using (DataAccessAdapterBase adapter=GetCompanyDataAccessAdapter()) { bool found=adapter.FetchEntity(_Company, prefetchPath, null, fieldList); if (!found) throw new Foundation.Common.RecordNotFoundException("Invalid Company"); } return _Company; } public EntityCollection GetCompanyCollection(IRelationPredicateBucket filterBucket) { return GetCompanyCollection(filterBucket,null); } public EntityCollection GetCompanyCollection(IRelationPredicateBucket filterBucket,ISortExpression sortExpression) { return GetCompanyCollection(filterBucket,sortExpression,null); } public EntityCollection GetCompanyCollection(IRelationPredicateBucket filterBucket,ISortExpression sortExpression, IPrefetchPath2 prefetchPath) { return GetCompanyCollection(filterBucket,sortExpression,prefetchPath,null); } public EntityCollection GetCompanyCollection(IRelationPredicateBucket filterBucket, ISortExpression sortExpression, IPrefetchPath2 prefetchPath, ExcludeIncludeFieldsList fieldList) { EntityCollection CompanyCollection =new EntityCollection(new CompanyEntityFactory()); using (DataAccessAdapterBase adapter =GetCompanyDataAccessAdapter()) { adapter.FetchEntityCollection(CompanyCollection, filterBucket, 0,sortExpression, prefetchPath, fieldList); } return CompanyCollection ; } public CompanyEntity SaveCompany(CompanyEntity Company) { return SaveCompany(Company,null); } public CompanyEntity SaveCompany(CompanyEntity Company ,EntityCollection entitiesToDelete) { return SaveCompany(Company,entitiesToDelete,string.Empty); } public CompanyEntity SaveCompany(CompanyEntity Company, EntityCollection entitiesToDelete, string seriesCode) { using (DataAccessAdapterBase adapter =GetCompanyDataAccessAdapter()) { try { adapter.StartTransaction(IsolationLevel.ReadCommitted, "SaveCompany"); adapter.SaveEntity(Company, true, false); adapter.Commit(); } catch { adapter.Rollback(); throw; } } return Company; } public void DeleteCompany(CompanyEntity Company) { using (DataAccessAdapterBase adapter =GetCompanyDataAccessAdapter()) { if (!adapter.IsEntityExist<CompanyEntity>(Company)) return; try { adapter.StartTransaction(IsolationLevel.ReadCommitted, "DeleteCompany"); adapter.DeleteEntity(Company); adapter.Commit(); } catch { adapter.Rollback(); throw; } } } public bool IsCompanyExist(System.String Companycode) { RelationPredicateBucket filterBucket = new RelationPredicateBucket(); filterBucket.PredicateExpression.Add(CompanyFields.Companycode==Companycode); return IsCompanyExist(filterBucket); } public bool IsCompanyExist(IRelationPredicateBucket filterBucket) { return (GetCompanyCount(filterBucket) > 0); } public int GetCompanyCount(IRelationPredicateBucket filterBucket) { using (DataAccessAdapterBase adapter =GetCompanyDataAccessAdapter()) { return adapter.GetDbCount<CompanyEntity>(filterBucket); } } public CompanyEntity CloneCompany(System.String Companycode) { CompanyEntity source = this.GetCompany(Companycode); CompanyEntity _Company = (CompanyEntity)CloneEntity(source); return _Company; } public void PostCompany(System.String Companycode) { return; } public void PostCompany(CompanyEntity Company) { return; } } }
有几个要注意的地方:
1 重载方法 满足不同的接口的需求。我这里实现的接口,相当于通用的接口方法,可以满足今后各种需求。
举例说明,增加一个字段,接口和实现不需要作任何改变。如果是只读取被增加的字段值,请传入参数ExcludeIncludeFieldsList以作为需要读取的值。
减少字段也不需要作任何的变更;如果删除了表,删除相应的Interface类型和Manager类型即可。
2 所有的CRUD的接口方法,均已经实现。
Create,Update => Save接口
Remove => Delete接口
UI 界面层代码生成
private ICompanyManager _CompanyManager = null ; private CompanyEntity _Company = null ; protected override void OnLoad(EventArgs e) { if(!DesignMode) this._CompanyManager = ClientProxyFactory.CreateProxyInstance<ICompanyManager>(); base.OnLoad(e); } protected override void InitNavigator(InitNavigatorArgs args) { base.InitNavigator(args); args.SortExpression.Add(CompanyFields.Companycode | SortOperator.Ascending); } protected override EntityBase2 LoadData(Dictionary<string, string> refNo) { base.LoadData(refNo); string Companycode=string.Empty; if(refNo.TryGetValue("Companycode", out Companycode)) { IPrefetchPath2 prefetchPath = new PrefetchPath2((int)EntityType.CompanyEntity); _Company = _CompanyManager.GetCompany(Companycode,prefetchPath); } else { _Company = new CompanyEntity(); } return _Company; } protected override void BindControls(EntityBase2 entity) { base.BindControls(entity); this.currencyBindingSource.DataSource = entity; } protected override EntityBase2 Add( ) { base.Add(); this._Company = new CompanyEntity(); return _Company; } protected override EntityBase2 Save(EntityBase2 entityToSave, EntityCollectionNonGeneric entitiesToDelete, string SeriesCode) { CompanyEntity _Company = (CompanyEntity)entityToSave; this._Company =this._CompanyManager.SaveCompany(_Company); return _Company; } protected override void Delete(EntityBase2 entityToDelete) { base.Delete(entityToDelete); CompanyEntity Company = (CompanyEntity)entityToDelete; this._CompanyManager.DeleteCompany(Company); } protected override object Clone(Dictionary<string, string> refNo) { base.Clone(refNo); string ccy = string.Empty; refNo.TryGetValue("Ccy", out ccy); return null; } protected override void ReleaseResources( ) { base.ReleaseResources(); try { _Company = null; _CompanyManager= null; } catch { } }
界面层的增删查改接口,数据绑定接口都已经生成。需要修改的地方,则是定制化代码的区域。比如增加一个公司时,它的创建日期应该为当前系统时间,创建人应该是当前登陆系统的用户。
Validation 验证代码
using System; using System.Collections.Generic; using System.Data; using System.Text; using SD.LLBLGen.Pro.ORMSupportClasses; using Foundation; using Foundation.FactoryClasses; using Foundation.EntityClasses; using Foundation.HelperClasses; using Foundation.InterfaceClasses; using Foundation.DatabaseSpecific; namespace Foundation.ValidatorClasses { [Serializable] public partial class CompanyEntityValidator : ValidatorBase { public override void ValidateEntityBeforeSave(IEntityCore involvedEntity) { base.ValidateEntityBeforeSave(involvedEntity); CompanyEntity company = (CompanyEntity)involvedEntity; if (company.IsNew) { } } public override void ValidateEntityBeforeDelete(IEntityCore involvedEntity) { base.ValidateEntityBeforeDelete(involvedEntity); CompanyEntity company = (CompanyEntity)involvedEntity; } public override bool ValidateFieldValue(IEntityCore involvedEntity, int fieldIndex, object value) { bool result = base.ValidateFieldValue(involvedEntity, fieldIndex, value); if (!result) return false; CompanyEntity company = (CompanyEntity)involvedEntity; switch ((CompanyFieldIndex)fieldIndex) { case SalesmanFieldIndex.Rank: return this.ValidateRank((decimal)value); case SalesmanFieldIndex.Supervisor: return this.ValidateSupervisor((string)value, salesman); } return true; } } }
数据的验证有二个方面,一个是实体层的验证,通常说的数据表的验证,常常是业务逻辑所需要。比如新增加一个公司时,输入公司的区域编码时,需要在系统的区域编码中验证一下,它的区域编码是否存在,如果不存在,则不允许保存。另一种验证是字段层的验证,比如输入公司联系方式的邮件地址时,需要验证邮件格式是否正确。
四种类型的接口,满足日常开发中所需要的大部分需求,再配合代码生成器,一天做十来个页面不是难事情,效率高,且质量也好,不会出错。