www.pudn.com > whpower2007-8-24.rar > SQLHelper.cs, change:2007-06-12,size:13135b


using System; 
using System.Configuration; 
using System.Data; 
using System.Data.SqlClient; 
using System.Collections; 
 
namespace com.etong.DBUtility 
{ 
    public abstract class SqlHelper 
    { 
 
        //Database connection strings 
        public static readonly string connectionString=ConfigurationManager.ConnectionStrings["connectionString"].ConnectionString; 
        //public static readonly string ConnectionStringInventoryDistributedTransaction = ConfigurationManager.ConnectionStrings["SQLConnString2"].ConnectionString; 
        //public static readonly string ConnectionStringOrderDistributedTransaction = ConfigurationManager.ConnectionStrings["SQLConnString3"].ConnectionString; 
        //public static readonly string ConnectionStringProfile = ConfigurationManager.ConnectionStrings["SQLProfileConnString"].ConnectionString; 
        // Hashtable to store cached parameters 
        private static 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> 
        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; 
            } 
        } 
 
        /// <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> 
        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; 
        } 
 
        /// <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> 
        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; 
        } 
 
        /// <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> 
        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; 
            } 
        } 
 
        public static DataSet ExecuteDataSet(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); 
                cmd.Connection = conn; 
                SqlDataAdapter da = new SqlDataAdapter(cmd); 
                try 
                { 
                    DataSet ds = new DataSet(); 
                    da.Fill(ds); 
                    return ds; 
                } 
                catch 
                { 
                    throw; 
                } 
                finally 
                { 
                    cmd.Parameters.Clear(); 
                } 
            } 
        } 
 
        public static DataTable ExecuteDataTable(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters) 
        { 
            DataSet ds = ExecuteDataSet(connectionString, cmdType, cmdText, commandParameters); 
            return (ds.Tables.Count > 0) ? ds.Tables[0] : null; 
        } 
 
 
 
        /// <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> 
        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; 
            } 
        } 
 
        /// <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> 
        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; 
        } 
 
        /// <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> 
        public static void 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> 
        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; 
        } 
 
        /// <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> 
        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); 
            } 
        } 
    } 
}