zoukankan      html  css  js  c++  java
  • Oracle Helper .NET 2.0 Class

    using System;
    using System.Configuration;
    using System.Data;
    using System.Data.OracleClient;
    using System.Collections;

    namespace DAL
    {

        /// <summary>
        /// A helper class used to execute queries against an Oracle database
        /// </summary>
        public abstract class OracleHelper {

            // Read the connection strings from the configuration file
            //public static readonly string ConnectionStringLocalTransaction = ConfigurationManager.ConnectionStrings["OraConnString1"].ConnectionString;
            //public static readonly string ConnectionStringInventoryDistributedTransaction = ConfigurationManager.ConnectionStrings["OraConnString2"].ConnectionString;
            //public static readonly string ConnectionStringOrderDistributedTransaction = ConfigurationManager.ConnectionStrings["OraConnString3"].ConnectionString;
            //public static readonly string ConnectionStringProfile = ConfigurationManager.ConnectionStrings["OraProfileConnString"].ConnectionString;
            //public static readonly string ConnectionStringMembership = ConfigurationManager.ConnectionStrings["OraMembershipConnString"].ConnectionString;

            //Create a hashtable for the parameter cached
            private static Hashtable parmCache = Hashtable.Synchronized(new Hashtable());

            /// <summary>
            /// Execute a database query which does not include a select
            /// </summary>
            /// <param name="connString">Connection string to database</param>
            /// <param name="cmdType">Command type either stored procedure or SQL</param>
            /// <param name="cmdText">Acutall SQL Command</param>
            /// <param name="commandParameters">Parameters to bind to the command</param>
            /// <returns></returns>
            public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) {
                // Create a new Oracle command
                OracleCommand cmd = new OracleCommand();

                //Create a connection
                using (OracleConnection connection = new OracleConnection(connectionString)) {

                    //Prepare the command
                    PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);

                    //Execute the command
                    int val = cmd.ExecuteNonQuery();
                    cmd.Parameters.Clear();
                    return val;
                }
            }

            /// <summary>
            /// Execute an OracleCommand (that returns no resultset) against an existing database transaction
            /// using the provided parameters.
            /// </summary>
            /// <remarks>
            /// e.g.: 
            ///  int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "PublishOrders", new OracleParameter(":prodid", 24));
            /// </remarks>
            /// <param name="trans">an existing database transaction</param>
            /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
            /// <param name="commandText">the stored procedure name or PL/SQL command</param>
            /// <param name="commandParameters">an array of OracleParamters used to execute the command</param>
            /// <returns>an int representing the number of rows affected by the command</returns>
            public static int ExecuteNonQuery(OracleTransaction trans, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) {
                OracleCommand cmd = new OracleCommand();
                PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, commandParameters);
                int val = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
                return val;
            }

            /// <summary>
            /// Execute an OracleCommand (that returns no resultset) against an existing database connection
            /// using the provided parameters.
            /// </summary>
            /// <remarks>
            /// e.g.: 
            ///  int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new OracleParameter(":prodid", 24));
            /// </remarks>
            /// <param name="conn">an existing database connection</param>
            /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
            /// <param name="commandText">the stored procedure name or PL/SQL command</param>
            /// <param name="commandParameters">an array of OracleParamters used to execute the command</param>
            /// <returns>an int representing the number of rows affected by the command</returns>
            public static int ExecuteNonQuery(OracleConnection connection, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) {

                OracleCommand cmd = new OracleCommand();

                PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
                int val = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
                return val;
            }

            /// <summary>
            /// Execute a select query that will return a result set
            /// </summary>
            /// <param name="connString">Connection string</param>
            //// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
            /// <param name="commandText">the stored procedure name or PL/SQL command</param>
            /// <param name="commandParameters">an array of OracleParamters used to execute the command</param>
            /// <returns></returns>
            public static OracleDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) {

                //Create the command and connection
                OracleCommand cmd = new OracleCommand();
                OracleConnection conn = new OracleConnection(connectionString);

                try {
                    //Prepare the command to execute
                    PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);

                    //Execute the query, stating that the connection should close when the resulting datareader has been read
                    OracleDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                    cmd.Parameters.Clear();
                    return rdr;

                }
                catch {

                    //If an error occurs close the connection as the reader will not be used and we expect it to close the connection
                    conn.Close();
                    throw;
                }
            }

            /// <summary>
            /// Execute an OracleCommand that returns the first column of the first record against the database specified in the connection string
            /// using the provided parameters.
            /// </summary>
            /// <remarks>
            /// e.g.: 
            ///  Object obj = ExecuteScalar(connString, CommandType.StoredProcedure, "PublishOrders", new OracleParameter(":prodid", 24));
            /// </remarks>
            /// <param name="connectionString">a valid connection string for a SqlConnection</param>
            /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
            /// <param name="commandText">the stored procedure name or PL/SQL command</param>
            /// <param name="commandParameters">an array of OracleParamters used to execute the command</param>
            /// <returns>An object that should be converted to the expected type using Convert.To{Type}</returns>
            public static object ExecuteScalar(string connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) {
                OracleCommand cmd = new OracleCommand();

                using (OracleConnection conn = new OracleConnection(connectionString)) {
                    PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
                    object val = cmd.ExecuteScalar();
                    cmd.Parameters.Clear();
                    return val;
                }
            }

            ///    <summary>
            ///    Execute    a OracleCommand (that returns a 1x1 resultset)    against    the    specified SqlTransaction
            ///    using the provided parameters.
            ///    </summary>
            ///    <param name="transaction">A    valid SqlTransaction</param>
            ///    <param name="commandType">The CommandType (stored procedure, text, etc.)</param>
            ///    <param name="commandText">The stored procedure name    or PL/SQL command</param>
            ///    <param name="commandParameters">An array of    OracleParamters used to execute the command</param>
            ///    <returns>An    object containing the value    in the 1x1 resultset generated by the command</returns>
            public static object ExecuteScalar(OracleTransaction transaction, CommandType commandType, string commandText, params OracleParameter[] commandParameters) {
                if(transaction == null)
                    throw new ArgumentNullException("transaction");
                if(transaction != null && transaction.Connection == null)
                    throw new ArgumentException("The transaction was rollbacked    or commited, please    provide    an open    transaction.", "transaction");

                // Create a    command    and    prepare    it for execution
                OracleCommand cmd = new OracleCommand();

                PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters);

                // Execute the command & return    the    results
                object retval = cmd.ExecuteScalar();

                // Detach the SqlParameters    from the command object, so    they can be    used again
                cmd.Parameters.Clear();
                return retval;
            }

            /// <summary>
            /// Execute an OracleCommand that returns the first column of the first record against an existing database connection
            /// using the provided parameters.
            /// </summary>
            /// <remarks>
            /// e.g.: 
            ///  Object obj = ExecuteScalar(conn, CommandType.StoredProcedure, "PublishOrders", new OracleParameter(":prodid", 24));
            /// </remarks>
            /// <param name="conn">an existing database connection</param>
            /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
            /// <param name="commandText">the stored procedure name or PL/SQL command</param>
            /// <param name="commandParameters">an array of OracleParamters used to execute the command</param>
            /// <returns>An object that should be converted to the expected type using Convert.To{Type}</returns>
            public static object ExecuteScalar(OracleConnection connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) {
                OracleCommand cmd = new OracleCommand();

                PrepareCommand(cmd, connectionString, null, cmdType, cmdText, commandParameters);
                object val = cmd.ExecuteScalar();
                cmd.Parameters.Clear();
                return val;
            }

            /// <summary>
            /// Add a set of parameters to the cached
            /// </summary>
            /// <param name="cacheKey">Key value to look up the parameters</param>
            /// <param name="commandParameters">Actual parameters to cached</param>
            public static void CacheParameters(string cacheKey, params OracleParameter[] commandParameters) {
                parmCache[cacheKey] = commandParameters;
            }

            /// <summary>
            /// Fetch parameters from the cache
            /// </summary>
            /// <param name="cacheKey">Key to look up the parameters</param>
            /// <returns></returns>
            public static OracleParameter[] GetCachedParameters(string cacheKey) {
                OracleParameter[] cachedParms = (OracleParameter[])parmCache[cacheKey];

                if (cachedParms == null)
                    return null;

                // If the parameters are in the cache
                OracleParameter[] clonedParms = new OracleParameter[cachedParms.Length];

                // return a copy of the parameters
                for (int i = 0, j = cachedParms.Length; i < j; i++)
                    clonedParms[i] = (OracleParameter)((ICloneable)cachedParms[i]).Clone();

                return clonedParms;
            }

            /// <summary>
            /// Internal function to prepare a command for execution by the database
            /// </summary>
            /// <param name="cmd">Existing command object</param>
            /// <param name="conn">Database connection object</param>
            /// <param name="trans">Optional transaction object</param>
            /// <param name="cmdType">Command type, e.g. stored procedure</param>
            /// <param name="cmdText">Command test</param>
            /// <param name="commandParameters">Parameters for the command</param>
            private static void PrepareCommand(OracleCommand cmd, OracleConnection conn, OracleTransaction trans, CommandType cmdType, string cmdText, OracleParameter[] commandParameters) {

                //Open the connection if required
                if (conn.State != ConnectionState.Open)
                    conn.Open();

                //Set up the command
                cmd.Connection = conn;
                cmd.CommandText = cmdText;
                cmd.CommandType = cmdType;

                //Bind it to the transaction if it exists
                if (trans != null)
                    cmd.Transaction = trans;

                // Bind the parameters passed in
                if (commandParameters != null) {
                    foreach (OracleParameter parm in commandParameters)
                        cmd.Parameters.Add(parm);
                }
            }

            /// <summary>
            /// Converter to use boolean data type with Oracle
            /// </summary>
            /// <param name="value">Value to convert</param>
            /// <returns></returns>
            public static string OraBit(bool value) {
                if(value)
                    return "Y";
                else
                    return "N";
            }

            /// <summary>
            /// Converter to use boolean data type with Oracle
            /// </summary>
            /// <param name="value">Value to convert</param>
            /// <returns></returns>
            public static bool OraBool(string value) {
                if(value.Equals("Y"))
                    return true;
                else
                    return false;
            }

            public static DataSet ExecuteDataSet(string ConnectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters)
            {
                //Create the command and connection
                OracleConnection conn = new OracleConnection(ConnectionString);
                conn.Open();
                OracleCommand cmd = new OracleCommand();
                cmd.Connection = conn;
                cmd.CommandText = cmdText;
                cmd.CommandType = CommandType.Text;
                OracleDataAdapter oda;
                //DataSet ds = new DataSet();
                DataSet ds;
                try
                {
                    oda = new OracleDataAdapter(cmd);
                    cmd.Connection.Open();
                    ds = new DataSet();
                    oda.Fill(ds, "temp");

                    ////Prepare the command to execute
                    //PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);

                    ////Execute the query, stating that the connection should close when the resulting datareader has been read
                    //OracleDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                    //cmd.Parameters.Clear();
                    conn.Close();
                    return ds;
                }
                catch (Exception err)
                {

                    //If an error occurs close the connection as the reader will not be used and we expect it to close the connection
                    conn.Close();
                    throw err;
                }
                //return ds;
            }
        }
    }
  • 相关阅读:
    poj 1080 dp
    Codeforces Round #280 (Div. 2)
    Codeforces Round #279 (Div. 2)f
    Codeforces Round #278 (Div. 1)
    Codeforces Round #276 (Div. 1)
    搜索
    debug 心得
    ZOJ 1633
    DRF 一对多序列化与反序列化
    HTTP协议
  • 原文地址:https://www.cnblogs.com/luluping/p/1583241.html
Copyright © 2011-2022 走看看