sqlhelper.cs

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				{
					connection.Open();
					SqlDataAdapter command = new SqlDataAdapter(SQLString,connection);				
					command.Fill(ds,startpage,pagesize,"ds");
				}
				catch(System.Data.SqlClient.SqlException ex)
				{				
					throw new Exception(ex.Message);
				}			
				return ds;
			}			
		}

        /// <summary>
        /// 判断是否链接数据库是否正常
        /// </summary>
        /// <returns></returns>
        public static bool TestDBConnection()
        {
            SqlConnection Conn = new SqlConnection(connectionString);
            try
            {
                
                Conn.Open();
            }
            catch (SqlException err)
            {
                throw new Exception(err.Message);
                
            }
            finally
            {
                if (Conn.State == ConnectionState.Open)
                    Conn.Close();
            }
            return true;
        }


		#endregion

		#region 执行带参数的SQL语句

		/// <summary>
		/// 执行SQL语句，返回影响的记录数
		/// </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	
	}
}