dbhelpersql.cs

主要实现软件的基本架构

		/// </summary>
		/// <param name="SQLString">SQL语句</param>
		/// <returns>影响的记录数</returns>
		public static int ExecuteSql(string SQLString,params SqlParameter[] cmdParms)
		{
			using (SqlConnection connection = new SqlConnection(connectionString))
			{				
				using (SqlCommand cmd = new SqlCommand())
				{
					try
					{		
						PrepareCommand(cmd, connection, null,SQLString, cmdParms);
						int rows=cmd.ExecuteNonQuery();
						cmd.Parameters.Clear();
						return rows;
					}
					catch(System.Data.SqlClient.SqlException E)
					{				
						throw new Exception(E.Message);
					}
				}				
			}
		}
		
			
		/// <summary>
		/// 执行多条SQL语句，实现数据库事务。
		/// </summary>
		/// <param name="SQLStringList">SQL语句的哈希表（key为sql语句，value是该语句的SqlParameter[]）</param>
		public static void ExecuteSqlTran(Hashtable SQLStringList)
		{			
			using (SqlConnection conn = new SqlConnection(connectionString))
			{
				conn.Open();
				using (SqlTransaction trans = conn.BeginTransaction()) 
				{
					SqlCommand cmd = new SqlCommand();
					try 
					{
						//循环
						foreach (DictionaryEntry myDE in SQLStringList)
						{	
							string 	cmdText=myDE.Key.ToString();
							SqlParameter[] cmdParms=(SqlParameter[])myDE.Value;
							PrepareCommand(cmd,conn,trans,cmdText, cmdParms);
							int val = cmd.ExecuteNonQuery();
							cmd.Parameters.Clear();

							trans.Commit();
						}					
					}
					catch 
					{
						trans.Rollback();
						throw;
					}
				}				
			}
		}
	
				
		/// <summary>
		/// 执行一条计算查询结果语句，返回查询结果（object）。
		/// </summary>
		/// <param name="SQLString">计算查询结果语句</param>
		/// <returns>查询结果（object）</returns>
		public static object GetSingle(string SQLString,params SqlParameter[] cmdParms)
		{
			using (SqlConnection connection = new SqlConnection(connectionString))
			{
				using (SqlCommand cmd = new SqlCommand())
				{
					try
					{
						PrepareCommand(cmd, connection, null,SQLString, cmdParms);
						object obj = cmd.ExecuteScalar();
						cmd.Parameters.Clear();
						if((Object.Equals(obj,null))||(Object.Equals(obj,System.DBNull.Value)))
						{					
							return null;
						}
						else
						{
							return obj;
						}				
					}
					catch(System.Data.SqlClient.SqlException e)
					{				
						throw new Exception(e.Message);
					}					
				}
			}
		}
		
		/// <summary>
		/// 执行查询语句，返回SqlDataReader
		/// </summary>
		/// <param name="strSQL">查询语句</param>
		/// <returns>SqlDataReader</returns>
		public static SqlDataReader ExecuteReader(string SQLString,params SqlParameter[] cmdParms)
		{		
			SqlConnection connection = new SqlConnection(connectionString);
			SqlCommand cmd = new SqlCommand();				
			try
			{
				PrepareCommand(cmd, connection, null,SQLString, cmdParms);
				SqlDataReader myReader = cmd.ExecuteReader();
				cmd.Parameters.Clear();
				return myReader;
			}
			catch(System.Data.SqlClient.SqlException e)
			{								
				throw new Exception(e.Message);
			}					
			
		}		
		
		/// <summary>
		/// 执行查询语句，返回DataSet
		/// </summary>
		/// <param name="SQLString">查询语句</param>
		/// <returns>DataSet</returns>
		public static DataSet Query(string SQLString,params SqlParameter[] cmdParms)
		{
			using (SqlConnection connection = new SqlConnection(connectionString))
			{
				SqlCommand cmd = new SqlCommand();
				PrepareCommand(cmd, connection, null,SQLString, cmdParms);
				using( SqlDataAdapter da = new SqlDataAdapter(cmd) )
				{
					DataSet ds = new DataSet();	
					try
					{												
						da.Fill(ds,"ds");
						cmd.Parameters.Clear();
					}
					catch(System.Data.SqlClient.SqlException ex)
					{				
						throw new Exception(ex.Message);
					}			
					return ds;
				}				
			}			
		}


		private static void PrepareCommand(SqlCommand cmd,SqlConnection conn,SqlTransaction trans, 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 = CommandType.Text;//cmdType;
			if (cmdParms != null) 
			{
				foreach (SqlParameter parm in cmdParms)
					cmd.Parameters.Add(parm);
			}
		}

		#endregion

		#region 存储过程操作

		/// <summary>
		/// 执行存储过程
		/// </summary>
		/// <param name="storedProcName">存储过程名</param>
		/// <param name="parameters">存储过程参数</param>
		/// <returns>SqlDataReader</returns>
		public static SqlDataReader RunProcedure(string storedProcName, IDataParameter[] parameters )
		{
			SqlConnection connection = new SqlConnection(connectionString);
			SqlDataReader returnReader;
			connection.Open();
			SqlCommand command = BuildQueryCommand( connection,storedProcName, parameters );
			command.CommandType = CommandType.StoredProcedure;
			returnReader = command.ExecuteReader();				
			return returnReader;			
		}
		
		
		/// <summary>
		/// 执行存储过程
		/// </summary>
		/// <param name="storedProcName">存储过程名</param>
		/// <param name="parameters">存储过程参数</param>
		/// <param name="tableName">DataSet结果中的表名</param>
		/// <returns>DataSet</returns>
		public static DataSet RunProcedure(string storedProcName, IDataParameter[] parameters, string tableName )
		{
			using (SqlConnection connection = new SqlConnection(connectionString))
			{
				DataSet dataSet = new DataSet();
				connection.Open();
				SqlDataAdapter sqlDA = new SqlDataAdapter();
				sqlDA.SelectCommand = BuildQueryCommand(connection, storedProcName, parameters );
				sqlDA.Fill( dataSet, tableName );
				connection.Close();
				return dataSet;
			}
		}

		
		/// <summary>
		/// 构建 SqlCommand 对象(用来返回一个结果集，而不是一个整数值)
		/// </summary>
		/// <param name="connection">数据库连接</param>
		/// <param name="storedProcName">存储过程名</param>
		/// <param name="parameters">存储过程参数</param>
		/// <returns>SqlCommand</returns>
		private static SqlCommand BuildQueryCommand(SqlConnection connection,string storedProcName, IDataParameter[] parameters)
		{			
			SqlCommand command = new SqlCommand( storedProcName, connection );
			command.CommandType = CommandType.StoredProcedure;
			foreach (SqlParameter parameter in parameters)
			{
				command.Parameters.Add( parameter );
			}
			return command;			
		}
		
		/// <summary>
		/// 执行存储过程，返回影响的行数		
		/// </summary>
		/// <param name="storedProcName">存储过程名</param>
		/// <param name="parameters">存储过程参数</param>
		/// <param name="rowsAffected">影响的行数</param>
		/// <returns></returns>
		public static int RunProcedure(string storedProcName, IDataParameter[] parameters, out int rowsAffected )
		{
			using (SqlConnection connection = new SqlConnection(connectionString))
			{
				int result;
				connection.Open();
				SqlCommand command = BuildIntCommand(connection,storedProcName, parameters );
				rowsAffected = command.ExecuteNonQuery();
				result = (int)command.Parameters["ReturnValue"].Value;
				//Connection.Close();
				return result;
			}
		}
		
		/// <summary>
		/// 创建 SqlCommand 对象实例(用来返回一个整数值)	
		/// </summary>
		/// <param name="storedProcName">存储过程名</param>
		/// <param name="parameters">存储过程参数</param>
		/// <returns>SqlCommand 对象实例</returns>
		private static SqlCommand BuildIntCommand(SqlConnection connection,string storedProcName, IDataParameter[] parameters)
		{
			SqlCommand command = BuildQueryCommand(connection,storedProcName, parameters );
			command.Parameters.Add( new SqlParameter ( "ReturnValue",
				SqlDbType.Int,4,ParameterDirection.ReturnValue,
				false,0,0,string.Empty,DataRowVersion.Default,null ));
			return command;
		}
		#endregion	

	}
}