//=============================================================================== // This file is based on the Microsoft Data Access Application Block for .NET // For more information please go to //http://msdn.microsoft.com/library/en-us/dnbda/html/daab-rm.asp //=============================================================================== using System; using System.Configuration; using System.Data; using System.Data.SqlClient; using System.Collections; namespace PetShop.DBUtility { /**////<summary> /// The SqlHelper class is intended to encapsulate high performance, /// scalable best practices for common uses of SqlClient. ///</summary> publicabstractclass SqlHelper { //Database connection strings publicstaticreadonlystring ConnectionStringLocalTransaction = ConfigurationManager.ConnectionStrings["SQLConnString1"].ConnectionString; publicstaticreadonlystring ConnectionStringInventoryDistributedTransaction = ConfigurationManager.ConnectionStrings["SQLConnString2"].ConnectionString; publicstaticreadonlystring ConnectionStringOrderDistributedTransaction = ConfigurationManager.ConnectionStrings["SQLConnString3"].ConnectionString; publicstaticreadonlystring ConnectionStringProfile = ConfigurationManager.ConnectionStrings["SQLProfileConnString"].ConnectionString; // Hashtable to store cached parameters privatestatic Hashtable parmCache = Hashtable.Synchronized(new Hashtable()); /**////<summary> /// Execute a SqlCommand (that returns no resultset) against the database specified in the connection string /// using the provided parameters. ///</summary> ///<remarks> /// e.g.: /// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@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 T-SQL command</param> ///<param name="commandParameters">an array of SqlParamters used to execute the command</param> ///<returns>an int representing the number of rows affected by the command</returns> publicstaticint 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> /// Execute a SqlCommand (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 SqlParameter("@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 T-SQL command</param> ///<param name="commandParameters">an array of SqlParamters used to execute the command</param> ///<returns>an int representing the number of rows affected by the command</returns> publicstaticint 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> /// Execute a SqlCommand (that returns no resultset) using an existing SQL Transaction /// using the provided parameters. ///</summary> ///<remarks> /// e.g.: /// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24)); ///</remarks> ///<param name="trans">an existing sql transaction</param> ///<param name="commandType">the CommandType (stored procedure, text, etc.)</param> ///<param name="commandText">the stored procedure name or T-SQL command</param> ///<param name="commandParameters">an array of SqlParamters used to execute the command</param> ///<returns>an int representing the number of rows affected by the command</returns> publicstaticint 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> /// Execute a SqlCommand that returns a resultset against the database specified in the connection string /// using the provided parameters. ///</summary> ///<remarks> /// e.g.: /// SqlDataReader r = ExecuteReader(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@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 T-SQL command</param> ///<param name="commandParameters">an array of SqlParamters used to execute the command</param> ///<returns>A SqlDataReader containing the results</returns> publicstatic 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; } } /**////<summary> /// Execute a SqlCommand 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 SqlParameter("@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 T-SQL command</param> ///<param name="commandParameters">an array of SqlParamters used to execute the command</param> ///<returns>An object that should be converted to the expected type using Convert.To{Type}</returns> publicstaticobject 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> /// Execute a SqlCommand 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(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@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 T-SQL command</param> ///<param name="commandParameters">an array of SqlParamters used to execute the command</param> ///<returns>An object that should be converted to the expected type using Convert.To{Type}</returns> publicstaticobject 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> /// add parameter array to the cache ///</summary> ///<param name="cacheKey">Key to the parameter cache</param> ///<param name="cmdParms">an array of SqlParamters to be cached</param> publicstaticvoid CacheParameters(string cacheKey, params SqlParameter[] commandParameters) { parmCache[cacheKey] = commandParameters; } /**////<summary> /// Retrieve cached parameters ///</summary> ///<param name="cacheKey">key used to lookup parameters</param> ///<returns>Cached SqlParamters array</returns> publicstatic SqlParameter[] GetCachedParameters(string cacheKey) { SqlParameter[] cachedParms = (SqlParameter[])parmCache[cacheKey]; if (cachedParms ==null) returnnull; 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> /// Prepare a command for execution ///</summary> ///<param name="cmd">SqlCommand object</param> ///<param name="conn">SqlConnection object</param> ///<param name="trans">SqlTransaction object</param> ///<param name="cmdType">Cmd type e.g. stored procedure or text</param> ///<param name="cmdText">Command text, e.g. Select * from Products</param> ///<param name="cmdParms">SqlParameters to use in the command</param> privatestaticvoid 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); } } } }