因为同志们一直给我提建议说，以前发的版本有问题。所以经过了我这一年多的使用和扩展，现在方法基本稳定了。现在贴出来给大家使用：
首先上场的是数据库操作层：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Linq.Expressions;
using System.Data.Objects.DataClasses;
using System.Reflection;
using JFrame.Utility;
namespace JFrame.AccessCommon
{
public class AccessBase<T> where T : EntityObject
{
protected string _TableName;
protected string _QueryColums;
protected string _PrimaryKey;
protected Type _PrimaryKeyType;
/// <summary>
/// 执行数据库操作基础类方法
/// </summary>
protected DataCommon Data;
/// <summary>
/// 实例化操作对象
/// </summary>
/// <param name="ConnectionString">EF连接字符串</param>
/// <param name="PrimaryKey">主键</param>
/// <param name="strTableName">表名</param>
/// <param name="QueryColums">查询的列</param>
/// <param name="IsEntityData">是否为ADO实体对象</param>
public AccessBase(string ConnectionString, string PrimaryKey = "", string strTableName = "", string QueryColums = "")
{
Data = new DataCommon(ConnectionString);
Type t = typeof(T);
if (string.IsNullOrEmpty(strTableName))
{
strTableName = t.Name; //GetType(t).ToString();
}
_TableName = strTableName;
if (string.IsNullOrEmpty(QueryColums))
{
_QueryColums = " * ";
}
if (string.IsNullOrEmpty(PrimaryKey))
{
PropertyInfo[] infos = t.GetProperties();
PrimaryKey = GetPrimaryKey(infos);
}
_PrimaryKey = PrimaryKey;
}
/// <summary>
/// 获取主键
/// </summary>
/// <param name="infos"></param>
/// <param name="IsEdmScalarPropertyAttribute"></param>
/// <returns></returns>
private string GetPrimaryKey(PropertyInfo[] infos)
{
string columnName = string.Empty;
foreach (PropertyInfo propertyInfo in infos)
{
object[] customInfos = propertyInfo.GetCustomAttributes(typeof(EdmScalarPropertyAttribute), true);
if (customInfos == null
|| customInfos.Length == 0)
return string.Empty;
EdmScalarPropertyAttribute limit = customInfos.GetValue(0) as EdmScalarPropertyAttribute;
if (limit.EntityKeyProperty)
{
_PrimaryKeyType = propertyInfo.PropertyType;
return columnName = propertyInfo.Name;
}
}
return columnName;
}
/// <summary>
/// 增加单个实体
/// </summary>
/// <param name="t"></param>
public virtual void AddEntity(T t)
{
Data.InsertEntity<T>(t);
}
/// <summary>
/// 获取单个实体
/// </summary>
/// <param name="query">查询条件</param>
/// <returns></returns>
public virtual T GetSingleEntity(Expression<Func<T, bool>> query)
{
return Data.GetSingleEntity<T>(query);
}
public virtual List<T> GetAllEntityByPage(Expression<Func<T, bool>> query,PagingInfo PageInfo, Func<T, object> orderByDesc)
{
return Data.GetAllEntity<T>(query, PageInfo, orderByDesc);
}
/// <summary>
/// 获取单个实体
/// </summary>
/// <typeparam name="T">泛型类型参数</typeparam>
/// <param name="express">查询条件</param>
/// <returns></returns>
public virtual T TryGetSingleEntity(Expression<Func<T, bool>> query)
{
try
{
return Data.GetSingleEntity<T>(query);
}
catch (Exception ex)
{
return null;
}
}
/// <summary>
/// 根据条件获取单个实体
/// </summary>
/// <param name="query">查询条件</param>
/// <returns>实体对象</returns>
public virtual T GetSingleEntity(string query)
{
return GetListByWhere(query).FirstOrDefault();
}
/// <summary>
/// 根据主键获取对象
/// </summary>
/// <param name="PrimaryKeyValue">主键值</param>
/// <returns>对象</returns>
public virtual T GetSingleEntity(object PrimaryKeyValue)
{
StringBuilder strWhere = new StringBuilder();
switch (_PrimaryKeyType.Name.ToLower())
{
case "int16":
case "int32":
case "int64":
case "int":
case "decimal":
case "double":
case "float":
case "short":
strWhere.AppendFormat(" {0}={1}", _PrimaryKey, PrimaryKeyValue);
break;
case "bool":
case "boolean":
if ((bool)PrimaryKeyValue)
{ strWhere.AppendFormat(" {0}=1", _PrimaryKey); }
else
{ strWhere.AppendFormat(" {0}=0", _PrimaryKey); }
break;
default:
strWhere.AppendFormat(" {0}=‘{1}‘", _PrimaryKey, PrimaryKeyValue);
break;
}
return GetListByWhere(strWhere.ToString()).FirstOrDefault();
}
/// <summary>
/// 修改单个实体
/// </summary>
/// <param name="t"></param>
public virtual void UpdateEntity(T t)
{
Type type = typeof(T);
PropertyInfo[] infos = type.GetProperties();
PropertyInfo info = infos.Where(p => p.Name == _PrimaryKey).FirstOrDefault();
object value = null;
if (info != null)
{
value = info.GetValue(t, null);
}
else
{
return;
}
Data.Update<T>(t, _PrimaryKey, value);
}
/// <summary>
/// 根据条件删除信息
/// </summary>
/// <param name="query">条件</param>
public virtual void Delete(Expression<Func<T, bool>> query)
{
Data.DeleteEntitys<T>(query);
}
/// <summary>
/// 根据条件获取相关信息表
/// </summary>
/// <param name="strWhere">Where条件</param>
/// <returns>数据集合</returns>
public virtual List<T> GetListByWhere(string strWhere)
{
StringBuilder strSql = new StringBuilder();
strSql.AppendFormat("select {1} from {0}", _TableName, _QueryColums);
if (!string.IsNullOrEmpty(strWhere))
{
strSql.AppendFormat(" where {0}", strWhere);
}
return Data.ExecuteQuery<T>(strSql.ToString()).ToList();
}
public virtual List<T> GetListByWhere()
{
return GetListByWhere(string.Empty);
}
/// <summary>
/// 根据条件获取相关信息
/// </summary>
/// <param name="strTableName">表名</param>
/// <param name="strColums">相关列（前面可加Top）</param>
/// <param name="strWhere">Where条件</param>
/// <returns>数据集合</returns>
public virtual List<T> GetListByWhere(string strTableName,string strColums,string strWhere,string strOrderBy)
{
StringBuilder strSql = new StringBuilder();
strSql.AppendFormat("select {1} from {0}", strTableName, strColums);
if (!string.IsNullOrEmpty(strWhere))
{
strSql.AppendFormat(" where {0}", strWhere);
}
if (!string.IsNullOrEmpty(strOrderBy))
{
strSql.AppendFormat(" Order by {0}", strOrderBy);
}
return Data.ExecuteQuery<T>(strSql.ToString()).ToList();
}
/// <summary>
/// 根据条件获取相关监测信息表
/// </summary>
/// <param name="strWhere">Where条件</param>
/// <returns>数据集合</returns>
public virtual List<T> GetListByWhere(Expression<Func<T, bool>> query)
{
return Data.GetAllEntity<T>(query);
}
/// <summary>
/// 获取列最大值
/// </summary>
/// <param name="CloumnName">列名</param>
/// <returns>最大值</returns>
public virtual object GetCloumnNameMaxValue<T2>(string CloumnName)
{
if (string.IsNullOrEmpty(CloumnName))
{
throw new Exception("列名值不能为空");
}
StringBuilder strSql = new StringBuilder();
strSql.AppendFormat("select max({1}) as val from {0}", _TableName, CloumnName);
return Data.ExecuteQuery<T2>(strSql.ToString()).FirstOrDefault();
}
/// <summary>
/// 获取最大主键
/// </summary>
/// <returns></returns>
protected virtual int? GetMaxPrimaryKey()
{
StringBuilder strSql = new StringBuilder();
strSql.AppendFormat("select max({1}) from {0}", _TableName, _PrimaryKey);
return Data.ExecuteQuery<int>(strSql.ToString()).FirstOrDefault();
}
}
}
Entity Framework底层操作封装V2版本（1）,布布扣,bubuko.com
原文地址：http://blog.csdn.net/jacky4955/article/details/25411239
