using System;using System.Configuration;using System.Data;using System.Data.SqlClient;using System.Collections;namespace Maticsoft.DBUtility{    /// 
    /// The SqlHelper class is intended to encapsulate high performance,     /// scalable best practices for common uses of SqlClient.    /// 
    public abstract class SqlHelper    {        //Database connection strings        public static readonly string ConnectionStringLocalTransaction =  ConfigurationManager.AppSettings["SQLConnString1"];        public static readonly string ConnectionStringInventoryDistributedTransaction =  ConfigurationManager.AppSettings["SQLConnString2"];        public static readonly string ConnectionStringOrderDistributedTransaction =  ConfigurationManager.AppSettings["SQLConnString3"];        public static readonly string ConnectionStringProfile =  ConfigurationManager.AppSettings["SQLProfileConnString"];        // Hashtable to store cached parameters        private static Hashtable parmCache = Hashtable.Synchronized(new Hashtable());        /// 
        /// Execute a SqlCommand (that returns no resultset) against the database specified in the connection string         /// using the provided parameters.        /// 
        /// 
    
             /// e.g.:          ///  int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));        /// 
            /// a valid connection string for a SqlConnection        /// the CommandType (stored procedure, text, etc.)        /// the stored procedure name or T-SQL command        /// an array of SqlParamters used to execute the command        /// 
    
     an int representing the number of rows affected by the command
            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;            }        }        /// 
        /// Execute a SqlCommand (that returns no resultset) against an existing database connection         /// using the provided parameters.        /// 
        /// 
    
             /// e.g.:          ///  int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));        /// 
            /// an existing database connection        /// the CommandType (stored procedure, text, etc.)        /// the stored procedure name or T-SQL command        /// an array of SqlParamters used to execute the command        /// 
    
     an int representing the number of rows affected by the command
            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;        }        /// 
        /// Execute a SqlCommand (that returns no resultset) using an existing SQL Transaction         /// using the provided parameters.        /// 
        /// 
    
             /// e.g.:          ///  int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));        /// 
            /// an existing sql transaction        /// the CommandType (stored procedure, text, etc.)        /// the stored procedure name or T-SQL command        /// an array of SqlParamters used to execute the command        /// 
    
     an int representing the number of rows affected by the command
            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;        }        /// 
        /// Execute a SqlCommand that returns a resultset against the database specified in the connection string         /// using the provided parameters.        /// 
        /// 
    
             /// e.g.:          ///  SqlDataReader r = ExecuteReader(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));        /// 
            /// a valid connection string for a SqlConnection        /// the CommandType (stored procedure, text, etc.)        /// the stored procedure name or T-SQL command        /// an array of SqlParamters used to execute the command        /// 
    
     A SqlDataReader containing the results
            public static SqlDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)        {            SqlCommand cmd = new SqlCommand();            SqlConnection conn = new SqlConnection(connectionString);            // we use a try/catch here because if the method throws an exception we want to             // close the connection throw code, because no datareader will exist, hence the             // commandBehaviour.CloseConnection will not work            try            {                PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);                SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);                cmd.Parameters.Clear();                return rdr;            }            catch            {                conn.Close();                throw;            }        }        /// 
        /// Execute a SqlCommand that returns the first column of the first record against the database specified in the connection string         /// using the provided parameters.        /// 
        /// 
    
             /// e.g.:          ///  Object obj = ExecuteScalar(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));        /// 
            /// a valid connection string for a SqlConnection        /// the CommandType (stored procedure, text, etc.)        /// the stored procedure name or T-SQL command        /// an array of SqlParamters used to execute the command        /// 
    
     An object that should be converted to the expected type using Convert.To{Type}
            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;            }        }        /// 
        /// Execute a SqlCommand that returns the first column of the first record against an existing database connection         /// using the provided parameters.        /// 
        /// 
    
             /// e.g.:          ///  Object obj = ExecuteScalar(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));        /// 
            /// an existing database connection        /// the CommandType (stored procedure, text, etc.)        /// the stored procedure name or T-SQL command        /// an array of SqlParamters used to execute the command        /// 
    
     An object that should be converted to the expected type using Convert.To{Type}
            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;        }        /// 
        /// add parameter array to the cache        /// 
        /// Key to the parameter cache        /// an array of SqlParamters to be cached        public static void CacheParameters(string cacheKey, params SqlParameter[] commandParameters)        {            parmCache[cacheKey] = commandParameters;        }        /// 
        /// Retrieve cached parameters        /// 
        /// key used to lookup parameters        /// 
    
     Cached SqlParamters array
            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;        }        /// 
        /// Prepare a command for execution        /// 
        /// SqlCommand object        /// SqlConnection object        /// SqlTransaction object        /// Cmd type e.g. stored procedure or text        /// Command text, e.g. Select * from Products        /// SqlParameters to use in the command        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);            }        }    }}