1 using System;  2 using System.Collections.Generic;  3 using System.Linq;  4 using System.Text;  5 using System.Data.Objects.DataClasses;  6 using ZBService.Model;  7 using System.Linq.Expressions;  8   9 namespace ZBService 10 { 11     public abstract class ServiceBase<T> where T:EntityObject 12     { 13         protected mZhaoBiaoEntities zbEntities = new mZhaoBiaoEntities(); 14  15         /// <summary> 16         /// 判断是否存在 17         /// </summary> 18         /// <param name="whereExpr"></param> 19         /// <returns></returns> 20         public bool Exist(Expression<Func<T,bool>> whereExpr) 21         { 22             return (this.Count(whereExpr) > 0); 23         } 24  25         /// <summary> 26         /// 获取记录数 27         /// </summary> 28         /// <param name="whereExpr"></param> 29         /// <returns></returns> 30         public int Count(Expression<Func<T, bool>> whereExpr) 31         { 32             return zbEntities.CreateObjectSet<T>().Where(whereExpr).Count(); 33         } 34  35         /// <summary> 36         /// 查找实体对象 37         /// </summary> 38         /// <param name="whereExpr"></param> 39         /// <returns></returns> 40         public T Find(Expression<Func<T, bool>> whereExpr) 41         { 42             return zbEntities.CreateObjectSet<T>().Where(whereExpr).FirstOrDefault(); 43         } 44  45         /// <summary> 46         /// 查找实体对象列表 47         /// </summary> 48         /// <param name="whereExpr"></param> 49         /// <returns></returns> 50         public IEnumerable<T> FindList<TKey>(Expression<Func<T, bool>> whereExpr, Expression<Func<T, TKey>> orderbyExpr, int orderDirection) 51         { 52             return this.FindList<T, TKey>(whereExpr,t=>t,orderbyExpr,orderDirection); 53         } 54  55         /// <summary> 56         /// 查找实体对象列表 57         /// </summary> 58         /// <typeparam name="TResult"></typeparam> 59         /// <typeparam name="TKey"></typeparam> 60         /// <param name="whereExpr"></param> 61         /// <param name="selectExpr"></param> 62         /// <param name="orderbyExpr"></param> 63         /// <param name="orderDirection"></param> 64         /// <param name="returnCount"></param> 65         /// <returns></returns> 66         public IEnumerable<TResult> FindList<TResult,TKey>(Expression<Func<T, bool>> whereExpr, Expression<Func<T, TResult>> selectExpr,Expression<Func<TResult,TKey>> orderbyExpr,int orderDirection,int returnCount=-1) 67         { 68             var result = zbEntities.CreateObjectSet<T>().Where(whereExpr).Select(selectExpr); 69             if (result != null && result.Count() > 0) 70             { 71                 if (returnCount > 0) 72                 { 73                     if (orderDirection > 0) 74                     { 75                         result = result.OrderByDescending(orderbyExpr).Take(returnCount); 76                     } 77                     else 78                     { 79                         result = result.OrderBy(orderbyExpr).Take(returnCount); 80                     } 81                 } 82                 return result.ToList(); 83             } 84             return null; 85         } 86  87         /// <summary> 88         /// 分页查找实体对象列表 89         /// </summary> 90         /// <typeparam name="TResult"></typeparam> 91         /// <typeparam name="TKey"></typeparam> 92         /// <param name="whereExpr"></param> 93         /// <param name="selectExpr"></param> 94         /// <param name="orderbyExpr"></param> 95         /// <param name="orderDirection"></param> 96         /// <param name="pageSize"></param> 97         /// <param name="pageNo"></param> 98         /// <param name="recordCount"></param> 99         /// <returns></returns>100         public IEnumerable<TResult> FindListByPage<TResult,TKey>(Expression<Func<T, bool>> whereExpr, Expression<Func<T, TResult>> selectExpr,Expression<Func<TResult,TKey>> orderbyExpr,int orderDirection,int pageSize,int pageNo,out int recordCount)101         {102             var result = zbEntities.CreateObjectSet<T>().Where(whereExpr).Select(selectExpr);103             recordCount = result.Count();104 105             if(pageNo>recordCount) pageNo=recordCount;106             if(pageNo<=0) pageNo=1;107 108             if (recordCount > 0)109             {110                 if (recordCount > pageSize)111                 {112                     if (orderDirection > 0)113                     {114                         return result.OrderByDescending(orderbyExpr).Skip((pageNo - 1) * pageSize).Take(pageSize).ToList();115                     }116                     else117                     {118                         return result.OrderBy(orderbyExpr).Skip((pageNo - 1) * pageSize).Take(pageSize).ToList();119                     }120                 }121                 else122                 {123                     if (orderDirection > 0)124                     {125                         return result.OrderByDescending(orderbyExpr).ToList();126                     }127                     else128                     {129                         return result.OrderBy(orderbyExpr).ToList();130                     }131                 }132                 133             }134             return null;135         }136 137 138 139 140         /// <summary>141         /// 增加实体142         /// </summary>143         /// <param name="entity"></param>144         public virtual void Add(T entity)145         {146             this.ValidateEntity(entity,ValidateMode.Add);147             zbEntities.CreateObjectSet<T>().AddObject(entity);148         }149 150 151         /// <summary>152         /// 增加实体列表153         /// </summary>154         /// <param name="entities"></param>155         public virtual void AddList(IEnumerable<T> entities)156         {157             var objSet = zbEntities.CreateObjectSet<T>();158             foreach (T entity in entities)159             {160                 this.ValidateEntity(entity, ValidateMode.Add);161                 objSet.AddObject(entity);162             }163         }164 165         /// <summary>166         /// 更新已分离实体,若未分离则不需要执行该方法167         /// </summary>168         /// <param name="entity"></param>169         public virtual void Update(T entity)170         {171             this.ValidateEntity(entity, ValidateMode.Update);172             zbEntities.CreateObjectSet<T>().ApplyCurrentValues(entity);173         }174 175         /// <summary>176         /// 删除实体177         /// </summary>178         /// <param name="entity"></param>179         public virtual void Delete(T entity)180         {181             this.ValidateEntity(entity, ValidateMode.Delete);182             zbEntities.CreateObjectSet<T>().DeleteObject(entity);183         }184 185         /// <summary>186         /// 删除实体187         /// </summary>188         /// <param name="whereExpr"></param>189         public virtual void Delete(Expression<Func<T, bool>> whereExpr)190         {191             var objSet = zbEntities.CreateObjectSet<T>();192             T entity = objSet.Where(whereExpr).Single();193             //this.ValidateEntity(entity, ValidateMode.Delete);194             objSet.DeleteObject(entity);195         }196 197         /// <summary>198         /// 删除实体列表199         /// </summary>200         /// <param name="entities"></param>201         public virtual void DeleteList(IEnumerable<T> entities)202         {203             var objSet = zbEntities.CreateObjectSet<T>();204             foreach (T entity in entities)205             {206                 //this.ValidateEntity(entity, ValidateMode.Delete);207                 objSet.DeleteObject(entity);208             }209         }210 211 212         /// <summary>213         /// 提交保存所有变更操作214         /// </summary>215         public void SubmitSave()216         {217             zbEntities.SaveChanges();218         }219 220 221         /// <summary>222         /// 验证223         /// </summary>224         /// <param name="entity"></param>225         /// <returns></returns>226         protected virtual void ValidateEntity(T entity,ValidateMode mode=ValidateMode.Add)227         {228 229         }230 231         /// <summary>232         /// 验证模式233         /// </summary>234         protected enum ValidateMode235         {236             Add=0,237             Update=1,238             Delete=-1239         }240 241     }242 }