//这是在网上找的中文解释的SqlHelper
using System;

using System.Configuration;

using System.Data;

using System.Data.SqlClient;

using System.Collections;

 

namespace com.DataAccess

{

 

    
/// <summary>

    
/// SqlHelper类提供很高的数据访问性能, 

    
/// 使用SqlClient类的通用定义.

    
/// </summary>

    
public abstract class SqlHelper

    {

 

        
//定义数据库连接串

        
public static readonly string ConnectionStringLocalTransaction = ConfigurationManager.ConnectionStrings["TestConnectionString"].ConnectionString;

        
//public static readonly string ConnectionStringInventoryDistributedTransaction = ConfigurationManager.ConnectionStrings["SQLConnString2"].ConnectionString;

        
//public static readonly string ConnectionStringOrderDistributedTransaction = ConfigurationManager.ConnectionStrings["SQLConnString3"].ConnectionString;

        
//public static readonly string ConnectionStringProfile = ConfigurationManager.ConnectionStrings["SQLProfileConnString"].ConnectionString;

 

        
// 存贮Cache缓存的Hashtable集合

        
private static Hashtable parmCache = Hashtable.Synchronized(new Hashtable());

 

        
/// <summary>

        
/// 使用连接字符串,执行一个SqlCommand命令(没有记录返回)

        
/// 使用提供的参数集.

        
/// </summary>

        
/// <remarks>

        
/// 示例:  

        
///  int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));

        
/// </remarks>

        
/// <param name="connectionString">一个有效的SqlConnection连接串</param>

        
/// <param name="commandType">命令类型CommandType(stored procedure, text, etc.)</param>

        
/// <param name="commandText">存贮过程名称或是一个T-SQL语句串</param>

        
/// <param name="commandParameters">执行命令的参数集</param>

        
/// <returns>受此命令影响的行数</returns>

        
public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

 

            SqlCommand cmd 
= new SqlCommand();

 

            
using (SqlConnection conn = new SqlConnection(connectionString))

            {

                PrepareCommand(cmd, conn, 
null, cmdType, cmdText, commandParameters);

                
int val = cmd.ExecuteNonQuery();

                cmd.Parameters.Clear();

                
return val;

            }

        }

 

        
/// <summary>

        
/// 在一个存在的连接上执行数据库的命令操作

        
/// 使用提供的参数集.

        
/// </summary>

        
/// <remarks>

        
/// e.g.:  

        
///  int result = ExecuteNonQuery(connection, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));

        
/// </remarks>

        
/// <param name="conn">一个存在的数据库连接对象</param>

        
/// <param name="commandType">命令类型CommandType (stored procedure, text, etc.)</param>

        
/// <param name="commandText">存贮过程名称或是一个T-SQL语句串</param>

        
/// <param name="commandParameters">执行命令的参数集</param>

        
/// <returns>受此命令影响的行数</returns>

        
public static int ExecuteNonQuery(SqlConnection connection, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

 

            SqlCommand cmd 
= new SqlCommand();

 

            PrepareCommand(cmd, connection, 
null, cmdType, cmdText, commandParameters);

            
int val = cmd.ExecuteNonQuery();

            cmd.Parameters.Clear();

            
return val;

        }

 

        
/// <summary>

        
/// 在一个事务的连接上执行数据库的命令操作

        
/// 使用提供的参数集.

        
/// </summary>

        
/// <remarks>

        
/// e.g.:  

        
///  int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));

        
/// </remarks>

        
/// <param name="trans">一个存在的事务</param>

        
/// <param name="commandType">命令类型CommandType (stored procedure, text, etc.)</param>

        
/// <param name="commandText">存贮过程名称或是一个T-SQL语句串</param>

        
/// <param name="commandParameters">执行命令的参数集</param>

        
/// <returns>受此命令影响的行数</returns>

        
public static int ExecuteNonQuery(SqlTransaction trans, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

            SqlCommand cmd 
= new SqlCommand();

            PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, commandParameters);

            
int val = cmd.ExecuteNonQuery();

            cmd.Parameters.Clear();

            
return val;

        }

 

        
/// <summary>

        
/// 在一个连接串上执行一个命令,返回一个SqlDataReader对象

        
/// 使用提供的参数.

        
/// </summary>

        
/// <remarks>

        
/// e.g.:  

        
///  SqlDataReader r = ExecuteReader(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));

        
/// </remarks>

        
/// <param name="connectionString">一个有效的SqlConnection连接串</param>

        
/// <param name="commandType">命令类型CommandType(stored procedure, text, etc.)</param>

        
/// <param name="commandText">存贮过程名称或是一个T-SQL语句串</param>

        
/// <param name="commandParameters">执行命令的参数集</param>

        
/// <returns>一个结果集对象SqlDataReader</returns>

        
public static SqlDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

            SqlCommand cmd 
= new SqlCommand();

            SqlConnection conn 
= new SqlConnection(connectionString);

 

            
// 如果不存在要查询的对象,则发生异常

            
// 连接要关闭

            
// CommandBehavior.CloseConnection在异常时不发生作用

            
try

            {

                PrepareCommand(cmd, conn, 
null, cmdType, cmdText, commandParameters);

                SqlDataReader rdr 
= cmd.ExecuteReader(CommandBehavior.CloseConnection);

                cmd.Parameters.Clear();

                
return rdr;

            }

            
catch

            {

                conn.Close();

                
throw;

            }

        }

 

        
/// <summary>

        
/// 在一个连接串上执行一个命令,返回表中第一行,第一列的值

        
/// 使用提供的参数.

        
/// </summary>

        
/// <remarks>

        
/// e.g.:  

        
///  Object obj = ExecuteScalar(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));

        
/// </remarks>

        
/// <param name="connectionString">一个有效的SqlConnection连接串</param>

        
/// <param name="commandType">命令类型CommandType(stored procedure, text, etc.)</param>

        
/// <param name="commandText">存贮过程名称或是一个T-SQL语句串</param>

        
/// <param name="commandParameters">执行命令的参数集</param>        /// <returns>返回的对象,在使用时记得类型转换</returns>

        
public static object ExecuteScalar(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

            SqlCommand cmd 
= new SqlCommand();

 

            
using (SqlConnection connection = new SqlConnection(connectionString))

            {

                PrepareCommand(cmd, connection, 
null, cmdType, cmdText, commandParameters);

                
object val = cmd.ExecuteScalar();

                cmd.Parameters.Clear();

                
return val;

            }

        }

 

        
/// <summary>

        
/// 在一个连接上执行一个命令,返回表中第一行,第一列的值

        
/// 使用提供的参数.

        
/// </summary>

        
/// <remarks>

        
/// e.g.:  

        
///  Object obj = ExecuteScalar(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));

        
/// </remarks>

        
/// <param name="connectionString">一个有效的SqlConnection连接</param>

        
/// <param name="commandType">命令类型CommandType(stored procedure, text, etc.)</param>

        
/// <param name="commandText">存贮过程名称或是一个T-SQL语句串</param>

        
/// <param name="commandParameters">执行命令的参数集</param>        /// <returns>返回的对象,在使用时记得类型转换</returns>

        
public static object ExecuteScalar(SqlConnection connection, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)

        {

 

            SqlCommand cmd 
= new SqlCommand();

 

            PrepareCommand(cmd, connection, 
null, cmdType, cmdText, commandParameters);

            
object val = cmd.ExecuteScalar();

            cmd.Parameters.Clear();

            
return val;

        }

 

        
/// <summary>

        
/// 在缓存中添加参数数组

        
/// </summary>

        
/// <param name="cacheKey">参数的Key</param>

        
/// <param name="cmdParms">参数数组</param>

        
public static void CacheParameters(string cacheKey, params SqlParameter[] commandParameters)

        {

            parmCache[cacheKey] 
= commandParameters;

        }

 

        
/// <summary>

        
/// 提取缓存的参数数组

        
/// </summary>

        
/// <param name="cacheKey">查找缓存的key</param>

        
/// <returns>返回被缓存的参数数组</returns>

        
public static SqlParameter[] GetCachedParameters(string cacheKey)

        {

            SqlParameter[] cachedParms 
= (SqlParameter[])parmCache[cacheKey];

 

            
if (cachedParms == null)

                
return null;

 

            SqlParameter[] clonedParms 
= new SqlParameter[cachedParms.Length];

 

            
for (int i = 0, j = cachedParms.Length; i < j; i++)

                clonedParms[i] 
= (SqlParameter)((ICloneable)cachedParms[i]).Clone();

 

            
return clonedParms;

        }

 

        
/// <summary>

        
/// 提供一个SqlCommand对象的设置

        
/// </summary>

        
/// <param name="cmd">SqlCommand对象</param>

        
/// <param name="conn">SqlConnection 对象</param>

        
/// <param name="trans">SqlTransaction 对象</param>

        
/// <param name="cmdType">CommandType 如存贮过程,T-SQL</param>

        
/// <param name="cmdText">存贮过程名或查询串</param>

        
/// <param name="cmdParms">命令中用到的参数集</param>

        
private static void PrepareCommand(SqlCommand cmd, SqlConnection conn, SqlTransaction trans, CommandType cmdType, string cmdText, SqlParameter[] cmdParms)

        {

 

            
if (conn.State != ConnectionState.Open)

                conn.Open();

 

            cmd.Connection 
= conn;

            cmd.CommandText 
= cmdText;

 

            
if (trans != null)

                cmd.Transaction 
= trans;

 

            cmd.CommandType 
= cmdType;

 

            
if (cmdParms != null)

            {

                
foreach (SqlParameter parm in cmdParms)

                    cmd.Parameters.Add(parm);

            }

        }

    }

}
posted on 2007-11-09 16:04  冷火  阅读(2759)  评论(0编辑  收藏  举报