Ferramentas de Usuário

Ferramentas de Site


dev_net:csharp:snippet:sqlhelper

C# SQL Helper

Classe para ajudar na realização de operações com a base de dados SQL Server!

using System;
using System.Data;
using System.Xml;
using System.Data.SqlClient;
using System.Collections;
using System.Globalization;
 
 
namespace HSS.Classes
{
	/// <summary>
	/// The SqlHelper class is intended to encapsulate high performance, scalable best practices for 
	/// common uses of SqlClient
	/// </summary>
    public sealed class SqlHelper
    {
        #region private utility methods & constructors
 
        // Since this class provides only static methods, make the default constructor private to prevent 
        // instances from being created with "new SqlHelper()"
        private SqlHelper() {}
 
        /// <summary>
        /// This method is used to attach array of SqlParameters to a SqlCommand.
        /// 
        /// This method will assign a value of DbNull to any parameter with a direction of
        /// InputOutput and a value of null.  
        /// 
        /// This behavior will prevent default values from being used, but
        /// this will be the less common case than an intended pure output parameter (derived as InputOutput)
        /// where the user provided no input value.
        /// </summary>
        /// <param name="command">The command to which the parameters will be added</param>
        /// <param name="commandParameters">An array of SqlParameters to be added to command</param>
        private static void AttachParameters(SqlCommand command, SqlParameter[] commandParameters)
        {
			if( command == null ) throw new ArgumentNullException( "command" );
			if( commandParameters != null )
			{
				foreach (SqlParameter p in commandParameters)
				{
					if( p != null )
					{
						// Check for derived output value with no value assigned
						if ( ( p.Direction == ParameterDirection.InputOutput || 
							p.Direction == ParameterDirection.Input ) && 
							(p.Value == null))
						{
							p.Value = DBNull.Value;
						}
						command.Parameters.Add(p);
					}
				}
			}
        }
 
        /// <summary>
        /// This method assigns dataRow column values to an array of SqlParameters
        /// </summary>
        /// <param name="commandParameters">Array of SqlParameters to be assigned values</param>
        /// <param name="dataRow">The dataRow used to hold the stored procedure's parameter values</param>
        private static void AssignParameterValues(SqlParameter[] commandParameters, DataRow dataRow)
        {
            if ((commandParameters == null) || (dataRow == null)) 
            {
                // Do nothing if we get no data
                return;
            }
 
			int i = 0;
            // Set the parameters values
            foreach(SqlParameter commandParameter in commandParameters)
            {
				// Check the parameter name
				if( commandParameter.ParameterName == null || 
					commandParameter.ParameterName.Length <= 1 )
					throw new System.Data.DataException( 
						string.Format(CultureInfo.CurrentCulture ,
							"Please provide a valid parameter name on the parameter #{0}, the ParameterName property has the following value: '{1}'.", 
							i, commandParameter.ParameterName ) );
                if (dataRow.Table.Columns.IndexOf(commandParameter.ParameterName.Substring(1)) != -1)
                    commandParameter.Value = dataRow[commandParameter.ParameterName.Substring(1)];
				i++;
            }
        }
 
        /// <summary>
        /// This method assigns an array of values to an array of SqlParameters
        /// </summary>
        /// <param name="commandParameters">Array of SqlParameters to be assigned values</param>
        /// <param name="parameterValues">Array of objects holding the values to be assigned</param>
        private static void AssignParameterValues(SqlParameter[] commandParameters, object[] parameterValues)
        {
            if ((commandParameters == null) || (parameterValues == null)) 
            {
                // Do nothing if we get no data
                return;
            }
 
 
            // We must have the same number of values as we pave parameters to put them in
            if (commandParameters.Length != parameterValues.Length)
            {
                throw new ArgumentException(String.Format(CultureInfo.CurrentCulture,"Parameter count does not match Parameter Value count.",null));
            }
 
            // Iterate through the SqlParameters, assigning the values from the corresponding position in the 
            // value array
            for (int i = 0, j = commandParameters.Length; i < j; i++)
            {
                // If the current array value derives from IDbDataParameter, then assign its Value property
				if (parameterValues[i] is IDbDataParameter)
				{
					IDbDataParameter paramInstance = (IDbDataParameter)parameterValues[i];
					if( paramInstance.Value == null )
					{
						commandParameters[i].Value = DBNull.Value; 
					}
					else
					{
						commandParameters[i].Value = paramInstance.Value;
					}
				}
				else if (parameterValues[i] == null)
				{
					commandParameters[i].Value = DBNull.Value;
				}
				else
				{
					commandParameters[i].Value = parameterValues[i];
				}
            }
        }
 
        /// <summary>
        /// This method opens (if necessary) and assigns a connection, transaction, command type and parameters 
        /// to the provided command
        /// </summary>
        /// <param name="command">The SqlCommand to be prepared</param>
        /// <param name="connection">A valid SqlConnection, on which to execute this command</param>
        /// <param name="transaction">A valid SqlTransaction, or 'null'</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 SqlParameters to be associated with the command or 'null' if no parameters are required</param>
        /// <param name="mustCloseConnection"><c>true</c> if the connection was opened by the method, otherwose is false.</param>
        private static void PrepareCommand(SqlCommand command, SqlConnection connection, SqlTransaction transaction, CommandType commandType, string commandText, SqlParameter[] commandParameters, out bool mustCloseConnection )
        {
			if( command == null ) throw new ArgumentNullException( "command" );
			if( commandText == null || commandText.Length == 0 ) throw new ArgumentNullException( "commandText" );
 
            // If the provided connection is not open, we will open it
			if (connection.State != ConnectionState.Open)
			{
				mustCloseConnection = true;
				connection.Open();
			}
			else
			{
				mustCloseConnection = false;
			}
 
            // Associate the connection with the command
            command.Connection = connection;
 
            // Set the command text (stored procedure name or SQL statement)
            command.CommandText = commandText;
 
            // If we were provided a transaction, assign it
            if (transaction != null)
            {
				if( transaction.Connection == null ) throw new ArgumentException( "The transaction was rollbacked or commited, please provide an open transaction.", "transaction" );
                command.Transaction = transaction;
            }
 
            // Set the command type
            command.CommandType = commandType;
 
            // Attach the command parameters if they are provided
            if (commandParameters != null)
            {
                AttachParameters(command, commandParameters);
            }
            return;
        }
 
        #endregion private utility methods & constructors
 
        #region ExecuteNonQuery
 
        /// <summary>
        /// Execute a SqlCommand (that returns no resultset and takes no parameters) against the database specified in 
        /// the connection string
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders");
        /// </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>
        /// <returns>An int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(string connectionString, CommandType commandType, string commandText)
        {
            // Pass through the call providing null for the set of SqlParameters
            return ExecuteNonQuery(connectionString, commandType, commandText, (SqlParameter[])null);
        }
 
        /// <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 commandType, string commandText, params SqlParameter[] commandParameters)
        {
			if( connectionString == null || connectionString.Length == 0 ) throw new ArgumentNullException( "connectionString" );
 
            // Create & open a SqlConnection, and dispose of it after we are done
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                connection.Open();
 
                // Call the overload that takes a connection in place of the connection string
                return ExecuteNonQuery(connection, commandType, commandText, commandParameters);
            }
        }
 
        /// <summary>
        /// Execute a stored procedure via a SqlCommand (that returns no resultset) against the database specified in 
        /// the connection string using the provided parameter values.  This method will query the database to discover the parameters for the 
        /// stored procedure (the first time each stored procedure is called), and assign the values based on parameter order.
        /// </summary>
        /// <remarks>
        /// This method provides no access to output parameters or the stored procedure's return value parameter.
        /// 
        /// e.g.:  
        ///  int result = ExecuteNonQuery(connString, "PublishOrders", 24, 36);
        /// </remarks>
        /// <param name="connectionString">A valid connection string for a SqlConnection</param>
        /// <param name="spName">The name of the stored prcedure</param>
        /// <param name="parameterValues">An array of objects to be assigned as the input values of the stored procedure</param>
        /// <returns>An int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(string connectionString, string spName, params object[] parameterValues)
        {
			if( connectionString == null || connectionString.Length == 0 ) throw new ArgumentNullException( "connectionString" );
			if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );
 
            // If we receive parameter values, we need to figure out where they go
            if ((parameterValues != null) && (parameterValues.Length > 0)) 
            {
                // Pull the parameters for this stored procedure from the parameter cache (or discover them & populate the cache)
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSPParameterSet(connectionString, spName);
 
                // Assign the provided values to these parameters based on parameter order
                AssignParameterValues(commandParameters, parameterValues);
 
                // Call the overload that takes an array of SqlParameters
                return ExecuteNonQuery(connectionString, CommandType.StoredProcedure, spName, commandParameters);
            }
            else 
            {
				// Otherwise we can just call the SP without params
                return ExecuteNonQuery(connectionString, CommandType.StoredProcedure, spName);
            }
        }
 
        /// <summary>
        /// Execute a SqlCommand (that returns no resultset and takes no parameters) against the provided SqlConnection. 
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders");
        /// </remarks>
        /// <param name="connection">A valid SqlConnection</param>
        /// <param name="commandType">The CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">The stored procedure name or T-SQL command</param>
        /// <returns>An int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(SqlConnection connection, CommandType commandType, string commandText)
        {
            // Pass through the call providing null for the set of SqlParameters
            return ExecuteNonQuery(connection, commandType, commandText, (SqlParameter[])null);
        }
 
        /// <summary>
        /// Execute a SqlCommand (that returns no resultset) against the specified SqlConnection 
        /// using the provided parameters.
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param name="connection">A valid 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(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
        {	
			if( connection == null ) throw new ArgumentNullException( "connection" );
 
            // Create a command and prepare it for execution
            SqlCommand cmd = new SqlCommand();
			bool mustCloseConnection = false;
            PrepareCommand(cmd, connection, (SqlTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection );
 
            // Finally, execute the command
            int retval = cmd.ExecuteNonQuery();
 
            // Detach the SqlParameters from the command object, so they can be used again
            cmd.Parameters.Clear();
			if( mustCloseConnection )
				connection.Close();
            return retval;
        }
 
        /// <summary>
        /// Execute a stored procedure via a SqlCommand (that returns no resultset) against the specified SqlConnection 
        /// using the provided parameter values.  This method will query the database to discover the parameters for the 
        /// stored procedure (the first time each stored procedure is called), and assign the values based on parameter order.
        /// </summary>
        /// <remarks>
        /// This method provides no access to output parameters or the stored procedure's return value parameter.
        /// 
        /// e.g.:  
        ///  int result = ExecuteNonQuery(conn, "PublishOrders", 24, 36);
        /// </remarks>
        /// <param name="connection">A valid SqlConnection</param>
        /// <param name="spName">The name of the stored procedure</param>
        /// <param name="parameterValues">An array of objects to be assigned as the input values of the stored procedure</param>
        /// <returns>An int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(SqlConnection connection, string spName, params object[] parameterValues)
        {
			if( connection == null ) throw new ArgumentNullException( "connection" );
			if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );
 
            // If we receive parameter values, we need to figure out where they go
            if ((parameterValues != null) && (parameterValues.Length > 0)) 
            {
                // Pull the parameters for this stored procedure from the parameter cache (or discover them & populate the cache)
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSPParameterSet(connection, spName);
 
                // Assign the provided values to these parameters based on parameter order
                AssignParameterValues(commandParameters, parameterValues);
 
                // Call the overload that takes an array of SqlParameters
                return ExecuteNonQuery(connection, CommandType.StoredProcedure, spName, commandParameters);
            }
            else 
            {
				// Otherwise we can just call the SP without params
                return ExecuteNonQuery(connection, CommandType.StoredProcedure, spName);
            }
        }
 
        /// <summary>
        /// Execute a SqlCommand (that returns no resultset and takes no parameters) against the provided SqlTransaction. 
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "PublishOrders");
        /// </remarks>
        /// <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 T-SQL command</param>
        /// <returns>An int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(SqlTransaction transaction, CommandType commandType, string commandText)
        {
            // Pass through the call providing null for the set of SqlParameters
            return ExecuteNonQuery(transaction, commandType, commandText, (SqlParameter[])null);
        }
 
        /// <summary>
        /// Execute a SqlCommand (that returns no resultset) against the specified SqlTransaction
        /// using the provided parameters.
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
        /// </remarks>
        /// <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 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 transaction, CommandType commandType, string commandText, params SqlParameter[] 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
			SqlCommand cmd = new SqlCommand();
			bool mustCloseConnection = false;
			PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection );
 
			// Finally, execute the command
			int retval = cmd.ExecuteNonQuery();
 
			// Detach the SqlParameters from the command object, so they can be used again
			cmd.Parameters.Clear();
			return retval;
		}
 
        /// <summary>
        /// Execute a stored procedure via a SqlCommand (that returns no resultset) against the specified 
        /// SqlTransaction using the provided parameter values.  This method will query the database to discover the parameters for the 
        /// stored procedure (the first time each stored procedure is called), and assign the values based on parameter order.
        /// </summary>
        /// <remarks>
        /// This method provides no access to output parameters or the stored procedure's return value parameter.
        /// 
        /// e.g.:  
        ///  int result = ExecuteNonQuery(conn, trans, "PublishOrders", 24, 36);
        /// </remarks>
        /// <param name="transaction">A valid SqlTransaction</param>
        /// <param name="spName">The name of the stored procedure</param>
        /// <param name="parameterValues">An array of objects to be assigned as the input values of the stored procedure</param>
        /// <returns>An int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(SqlTransaction transaction, string spName, params object[] parameterValues)
        {
			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" );
			if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );
 
			// If we receive parameter values, we need to figure out where they go
            if ((parameterValues != null) && (parameterValues.Length > 0)) 
            {
                // Pull the parameters for this stored procedure from the parameter cache (or discover them & populate the cache)
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSPParameterSet(transaction.Connection, spName);
 
                // Assign the provided values to these parameters based on parameter order
                AssignParameterValues(commandParameters, parameterValues);
 
                // Call the overload that takes an array of SqlParameters
                return ExecuteNonQuery(transaction, CommandType.StoredProcedure, spName, commandParameters);
            }
            else 
            {
				// Otherwise we can just call the SP without params
                return ExecuteNonQuery(transaction, CommandType.StoredProcedure, spName);
            }
        }
 
        #endregion ExecuteNonQuery
 
        #region ExecuteDataSet
 
        /// <summary>
        /// Execute a SqlCommand (that returns a resultset and takes no parameters) against the database specified in 
        /// the connection string. 
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  DataSet ds = ExecuteDataSet(connString, CommandType.StoredProcedure, "GetOrders");
        /// </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>
        /// <returns>A dataset containing the resultset generated by the command</returns>
        public static DataSet ExecuteDataSet(string connectionString, CommandType commandType, string commandText)
        {
            // Pass through the call providing null for the set of SqlParameters
            return ExecuteDataSet(connectionString, commandType, commandText, (SqlParameter[])null);
        }
 
        /// <summary>
        /// Execute a SqlCommand (that returns a resultset) against the database specified in the connection string 
        /// using the provided parameters.
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  DataSet ds = ExecuteDataSet(connString, CommandType.StoredProcedure, "GetOrders", 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 dataset containing the resultset generated by the command</returns>
        public static DataSet ExecuteDataSet(string connectionString, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
        {
			if( connectionString == null || connectionString.Length == 0 ) throw new ArgumentNullException( "connectionString" );
 
            // Create & open a SqlConnection, and dispose of it after we are done
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                connection.Open();
 
                // Call the overload that takes a connection in place of the connection string
                return ExecuteDataSet(connection, commandType, commandText, commandParameters);
            }
        }
 
        /// <summary>
        /// Execute a stored procedure via a SqlCommand (that returns a resultset) against the database specified in 
        /// the connection string using the provided parameter values.  This method will query the database to discover the parameters for the 
        /// stored procedure (the first time each stored procedure is called), and assign the values based on parameter order.
        /// </summary>
        /// <remarks>
        /// This method provides no access to output parameters or the stored procedure's return value parameter.
        /// 
        /// e.g.:  
        ///  DataSet ds = ExecuteDataSet(connString, "GetOrders", 24, 36);
        /// </remarks>
        /// <param name="connectionString">A valid connection string for a SqlConnection</param>
        /// <param name="spName">The name of the stored procedure</param>
        /// <param name="parameterValues">An array of objects to be assigned as the input values of the stored procedure</param>
        /// <returns>A dataset containing the resultset generated by the command</returns>
        public static DataSet ExecuteDataSet(string connectionString, string spName, params object[] parameterValues)
        {
			if( connectionString == null || connectionString.Length == 0 ) throw new ArgumentNullException( "connectionString" );
			if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );
 
			// If we receive parameter values, we need to figure out where they go
            if ((parameterValues != null) && (parameterValues.Length > 0)) 
            {
                // Pull the parameters for this stored procedure from the parameter cache (or discover them & populate the cache)
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSPParameterSet(connectionString, spName);
 
                // Assign the provided values to these parameters based on parameter order
                AssignParameterValues(commandParameters, parameterValues);
 
                // Call the overload that takes an array of SqlParameters
                return ExecuteDataSet(connectionString, CommandType.StoredProcedure, spName, commandParameters);
            }
            else 
            {
				// Otherwise we can just call the SP without params
                return ExecuteDataSet(connectionString, CommandType.StoredProcedure, spName);
            }
        }
 
        /// <summary>
        /// Execute a SqlCommand (that returns a resultset and takes no parameters) against the provided SqlConnection. 
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  DataSet ds = ExecuteDataSet(conn, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param name="connection">A valid SqlConnection</param>
        /// <param name="commandType">The CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">The stored procedure name or T-SQL command</param>
        /// <returns>A dataset containing the resultset generated by the command</returns>
        public static DataSet ExecuteDataSet(SqlConnection connection, CommandType commandType, string commandText)
        {
            // Pass through the call providing null for the set of SqlParameters
            return ExecuteDataSet(connection, commandType, commandText, (SqlParameter[])null);
        }
 
        /// <summary>
        /// Execute a SqlCommand (that returns a resultset) against the specified SqlConnection 
        /// using the provided parameters.
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  DataSet ds = ExecuteDataSet(conn, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param name="connection">A valid 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 dataset containing the resultset generated by the command</returns>
		public static DataSet ExecuteDataSet(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
		{
			if( connection == null ) throw new ArgumentNullException( "connection" );
 
			// Create a command and prepare it for execution
			SqlCommand cmd = new SqlCommand();
			bool mustCloseConnection = false;
			PrepareCommand(cmd, connection, (SqlTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection );
 
			// Create the DataAdapter & DataSet
			using( SqlDataAdapter da = new SqlDataAdapter(cmd) )
			{
				DataSet ds = new DataSet();
				ds.Locale=CultureInfo.CurrentCulture;
 
				// Fill the DataSet using default values for DataTable names, etc
				da.Fill(ds);
 
				// Detach the SqlParameters from the command object, so they can be used again
				cmd.Parameters.Clear();
 
				if( mustCloseConnection )
					connection.Close();
 
				// Return the dataset
				return ds;
			}	
		}
 
        /// <summary>
        /// Execute a stored procedure via a SqlCommand (that returns a resultset) against the specified SqlConnection 
        /// using the provided parameter values.  This method will query the database to discover the parameters for the 
        /// stored procedure (the first time each stored procedure is called), and assign the values based on parameter order.
        /// </summary>
        /// <remarks>
        /// This method provides no access to output parameters or the stored procedure's return value parameter.
        /// 
        /// e.g.:  
        ///  DataSet ds = ExecuteDataSet(conn, "GetOrders", 24, 36);
        /// </remarks>
        /// <param name="connection">A valid SqlConnection</param>
        /// <param name="spName">The name of the stored procedure</param>
        /// <param name="parameterValues">An array of objects to be assigned as the input values of the stored procedure</param>
        /// <returns>A dataset containing the resultset generated by the command</returns>
        public static DataSet ExecuteDataSet(SqlConnection connection, string spName, params object[] parameterValues)
        {
			if( connection == null ) throw new ArgumentNullException( "connection" );
			if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );
 
            // If we receive parameter values, we need to figure out where they go
            if ((parameterValues != null) && (parameterValues.Length > 0)) 
            {
                // Pull the parameters for this stored procedure from the parameter cache (or discover them & populate the cache)
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSPParameterSet(connection, spName);
 
                // Assign the provided values to these parameters based on parameter order
                AssignParameterValues(commandParameters, parameterValues);
 
                // Call the overload that takes an array of SqlParameters
                return ExecuteDataSet(connection, CommandType.StoredProcedure, spName, commandParameters);
            }
            else 
            {
				// Otherwise we can just call the SP without params
                return ExecuteDataSet(connection, CommandType.StoredProcedure, spName);
            }
        }
 
        /// <summary>
        /// Execute a SqlCommand (that returns a resultset and takes no parameters) against the provided SqlTransaction. 
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  DataSet ds = ExecuteDataSet(trans, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <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 T-SQL command</param>
        /// <returns>A dataset containing the resultset generated by the command</returns>
        public static DataSet ExecuteDataSet(SqlTransaction transaction, CommandType commandType, string commandText)
        {
            // Pass through the call providing null for the set of SqlParameters
            return ExecuteDataSet(transaction, commandType, commandText, (SqlParameter[])null);
        }
 
        /// <summary>
        /// Execute a SqlCommand (that returns a resultset) against the specified SqlTransaction
        /// using the provided parameters.
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  DataSet ds = ExecuteDataSet(trans, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
        /// </remarks>
        /// <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 T-SQL command</param>
        /// <param name="commandParameters">An array of SqlParamters used to execute the command</param>
        /// <returns>A dataset containing the resultset generated by the command</returns>
		public static DataSet ExecuteDataSet(SqlTransaction transaction, CommandType commandType, string commandText, params SqlParameter[] 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
			SqlCommand cmd = new SqlCommand();
			bool mustCloseConnection = false;
			PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection );
 
			// Create the DataAdapter & DataSet
			using( SqlDataAdapter da = new SqlDataAdapter(cmd) )
			{
				DataSet ds = new DataSet();
				ds.Locale=CultureInfo.CurrentCulture;
 
				// Fill the DataSet using default values for DataTable names, etc
				da.Fill(ds);
 
				// Detach the SqlParameters from the command object, so they can be used again
				cmd.Parameters.Clear();
 
				// Return the dataset
				return ds;
			}	
		}
 
        /// <summary>
        /// Execute a stored procedure via a SqlCommand (that returns a resultset) against the specified 
        /// SqlTransaction using the provided parameter values.  This method will query the database to discover the parameters for the 
        /// stored procedure (the first time each stored procedure is called), and assign the values based on parameter order.
        /// </summary>
        /// <remarks>
        /// This method provides no access to output parameters or the stored procedure's return value parameter.
        /// 
        /// e.g.:  
        ///  DataSet ds = ExecuteDataSet(trans, "GetOrders", 24, 36);
        /// </remarks>
        /// <param name="transaction">A valid SqlTransaction</param>
        /// <param name="spName">The name of the stored procedure</param>
        /// <param name="parameterValues">An array of objects to be assigned as the input values of the stored procedure</param>
        /// <returns>A dataset containing the resultset generated by the command</returns>
        public static DataSet ExecuteDataSet(SqlTransaction transaction, string spName, params object[] parameterValues)
        {
			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" );
			if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );
 
			// If we receive parameter values, we need to figure out where they go
            if ((parameterValues != null) && (parameterValues.Length > 0)) 
            {
                // Pull the parameters for this stored procedure from the parameter cache (or discover them & populate the cache)
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSPParameterSet(transaction.Connection, spName);
 
                // Assign the provided values to these parameters based on parameter order
                AssignParameterValues(commandParameters, parameterValues);
 
                // Call the overload that takes an array of SqlParameters
                return ExecuteDataSet(transaction, CommandType.StoredProcedure, spName, commandParameters);
            }
            else 
            {
				// Otherwise we can just call the SP without params
                return ExecuteDataSet(transaction, CommandType.StoredProcedure, spName);
            }
        }
 
        #endregion ExecuteDataSet
 
        #region ExecuteReader
 
        /// <summary>
        /// This enum is used to indicate whether the connection was provided by the caller, or created by SqlHelper, so that
        /// we can set the appropriate CommandBehavior when calling ExecuteReader()
        /// </summary>
        private enum SqlConnectionOwnership	
        {
            /// <summary>Connection is owned and managed by SqlHelper</summary>
            Internal, 
            /// <summary>Connection is owned and managed by the caller</summary>
            External
        }
 
        /// <summary>
        /// Create and prepare a SqlCommand, and call ExecuteReader with the appropriate CommandBehavior.
        /// </summary>
        /// <remarks>
        /// If we created and opened the connection, we want the connection to be closed when the DataReader is closed.
        /// 
        /// If the caller provided the connection, we want to leave it to them to manage.
        /// </remarks>
        /// <param name="connection">A valid SqlConnection, on which to execute this command</param>
        /// <param name="transaction">A valid SqlTransaction, or 'null'</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 SqlParameters to be associated with the command or 'null' if no parameters are required</param>
        /// <param name="connectionOwnership">Indicates whether the connection parameter was provided by the caller, or created by SqlHelper</param>
        /// <returns>SqlDataReader containing the results of the command</returns>
        private static SqlDataReader ExecuteReader(SqlConnection connection, SqlTransaction transaction, CommandType commandType, string commandText, SqlParameter[] commandParameters, SqlConnectionOwnership connectionOwnership)
        {	
			if( connection == null ) throw new ArgumentNullException( "connection" );
 
			bool mustCloseConnection = false;
            // Create a command and prepare it for execution
            SqlCommand cmd = new SqlCommand();
			try
			{
				PrepareCommand(cmd, connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection );
 
				// Create a reader
				SqlDataReader dataReader;
 
				// Call ExecuteReader with the appropriate CommandBehavior
				if (connectionOwnership == SqlConnectionOwnership.External)
				{
					dataReader = cmd.ExecuteReader();
				}
				else
				{
					dataReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
				}
 
				// Detach the SqlParameters from the command object, so they can be used again.
				// HACK: There is a problem here, the output parameter values are fletched 
				// when the reader is closed, so if the parameters are detached from the command
				// then the SqlReader can´t set its values. 
				// When this happen, the parameters can´t be used again in other command.
				bool canClear = true;
				foreach(SqlParameter commandParameter in cmd.Parameters)
				{
					if (commandParameter.Direction != ParameterDirection.Input)
						canClear = false;
				}
 
				if (canClear)
				{
					cmd.Parameters.Clear();
				}
 
				return dataReader;
			}
			catch
			{
				if( mustCloseConnection )
					connection.Close();
				throw;
			}
        }
 
        /// <summary>
        /// Execute a SqlCommand (that returns a resultset and takes no parameters) against the database specified in 
        /// the connection string. 
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  SqlDataReader dr = ExecuteReader(connString, CommandType.StoredProcedure, "GetOrders");
        /// </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>
        /// <returns>A SqlDataReader containing the resultset generated by the command</returns>
        public static SqlDataReader ExecuteReader(string connectionString, CommandType commandType, string commandText)
        {
            // Pass through the call providing null for the set of SqlParameters
            return ExecuteReader(connectionString, commandType, commandText, (SqlParameter[])null);
        }
 
dev_net/csharp/snippet/sqlhelper.txt · Última modificação em: 2018/05/14 21:37 (edição externa)