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  • C#操作SQLite数据库

    using System;
    using System.Data.SQLite;
    
    namespace SQLiteSamples
    {
        class Program
        {
            //数据库连接
            SQLiteConnection m_dbConnection;
    
            static void Main(string[] args)
            {
                Program p = new Program();
            }
    
            public Program()
            {
                createNewDatabase();
                connectToDatabase();
                createTable();
                fillTable();
                printHighscores();
            }
    
            //创建一个空的数据库
            void createNewDatabase()
            {
                SQLiteConnection.CreateFile("MyDatabase.sqlite");
            }
    
            //创建一个连接到指定数据库
            void connectToDatabase()
            {
                m_dbConnection = new SQLiteConnection("Data Source=MyDatabase.sqlite;Version=3;");
                m_dbConnection.Open();
            }
    
            //在指定数据库中创建一个table
            void createTable()
            {
                string sql = "create table highscores (name varchar(20), score int)";
                SQLiteCommand command = new SQLiteCommand(sql, m_dbConnection);
                command.ExecuteNonQuery();
            }
    
            //插入一些数据
            void fillTable()
            {
                string sql = "insert into highscores (name, score) values ('Me', 3000)";
                SQLiteCommand command = new SQLiteCommand(sql, m_dbConnection);
                command.ExecuteNonQuery();
    
                sql = "insert into highscores (name, score) values ('Myself', 6000)";
                command = new SQLiteCommand(sql, m_dbConnection);
                command.ExecuteNonQuery();
    
                sql = "insert into highscores (name, score) values ('And I', 9001)";
                command = new SQLiteCommand(sql, m_dbConnection);
                command.ExecuteNonQuery();
            }
    
            //使用sql查询语句,并显示结果
            void printHighscores()
            {
                string sql = "select * from highscores order by score desc";
                SQLiteCommand command = new SQLiteCommand(sql, m_dbConnection);
                SQLiteDataReader reader = command.ExecuteReader();
                while (reader.Read())
                    Console.WriteLine("Name: " + reader["name"] + "	Score: " + reader["score"]);
                Console.ReadLine();
            }
        }
    }
    using System;
    using System.Data;
    using System.Text.RegularExpressions;
    using System.Xml;
    using System.IO;
    using System.Collections;
    using System.Data.SQLite;
    
    namespace DBUtility.SQLite
    {
        /// <summary>
        /// SQLiteHelper is a utility class similar to "SQLHelper" in MS
        /// Data Access Application Block and follows similar pattern.
        /// </summary>
        public class SQLiteHelper
        {
            /// <summary>
            /// Creates a new <see cref="SQLiteHelper"/> instance. The ctor is marked private since all members are static.
            /// </summary>
            private SQLiteHelper()
            {
            }
            /// <summary>
            /// Creates the command.
            /// </summary>
            /// <param name="connection">Connection.</param>
            /// <param name="commandText">Command text.</param>
            /// <param name="commandParameters">Command parameters.</param>
            /// <returns>SQLite Command</returns>
            public static SQLiteCommand CreateCommand(SQLiteConnection connection, string commandText, params SQLiteParameter[] commandParameters)
            {
                SQLiteCommand cmd = new SQLiteCommand(commandText, connection);
                if (commandParameters.Length > 0)
                {
                    foreach (SQLiteParameter parm in commandParameters)
                        cmd.Parameters.Add(parm);
                }
                return cmd;
            }
    
            /// <summary>
            /// Creates the command.
            /// </summary>
            /// <param name="connectionString">Connection string.</param>
            /// <param name="commandText">Command text.</param>
            /// <param name="commandParameters">Command parameters.</param>
            /// <returns>SQLite Command</returns>
            public static SQLiteCommand CreateCommand(string connectionString, string commandText, params SQLiteParameter[] commandParameters)
            {
                SQLiteConnection cn = new SQLiteConnection(connectionString);
    
                SQLiteCommand cmd = new SQLiteCommand(commandText, cn);
    
                if (commandParameters.Length > 0)
                {
                    foreach (SQLiteParameter parm in commandParameters)
                        cmd.Parameters.Add(parm);
                }
                return cmd;
            }
            /// <summary>
            /// Creates the parameter.
            /// </summary>
            /// <param name="parameterName">Name of the parameter.</param>
            /// <param name="parameterType">Parameter type.</param>
            /// <param name="parameterValue">Parameter value.</param>
            /// <returns>SQLiteParameter</returns>
            public static SQLiteParameter CreateParameter(string parameterName, System.Data.DbType parameterType, object parameterValue)
            {
                SQLiteParameter parameter = new SQLiteParameter();
                parameter.DbType = parameterType;
                parameter.ParameterName = parameterName;
                parameter.Value = parameterValue;
                return parameter;
            }
    
            /// <summary>
            /// Shortcut method to execute dataset from SQL Statement and object[] arrray of parameter values
            /// </summary>
            /// <param name="connectionString">SQLite Connection string</param>
            /// <param name="commandText">SQL Statement with embedded "@param" style parameter names</param>
            /// <param name="paramList">object[] array of parameter values</param>
            /// <returns></returns>
            public static DataSet ExecuteDataSet(string connectionString, string commandText, object[] paramList)
            {
                SQLiteConnection cn = new SQLiteConnection(connectionString);
                SQLiteCommand cmd = cn.CreateCommand();
    
    
                cmd.CommandText = commandText;
                if (paramList != null)
                {
                    AttachParameters(cmd,commandText, paramList);
                }
                DataSet ds = new DataSet();
                if (cn.State == ConnectionState.Closed)
                    cn.Open();
                SQLiteDataAdapter da = new SQLiteDataAdapter(cmd);
                da.Fill(ds);
                da.Dispose();
                cmd.Dispose();
                cn.Close();
                return ds;
            }
            /// <summary>
            /// Shortcut method to execute dataset from SQL Statement and object[] arrray of  parameter values
            /// </summary>
            /// <param name="cn">Connection.</param>
            /// <param name="commandText">Command text.</param>
            /// <param name="paramList">Param list.</param>
            /// <returns></returns>
            public static DataSet ExecuteDataSet(SQLiteConnection cn, string commandText, object[] paramList)
            {
    
                SQLiteCommand cmd = cn.CreateCommand();
    
    
                cmd.CommandText = commandText;
                if (paramList != null)
                {
                    AttachParameters(cmd,commandText, paramList);
                }
                DataSet ds = new DataSet();
                if (cn.State == ConnectionState.Closed)
                    cn.Open();
                SQLiteDataAdapter da = new SQLiteDataAdapter(cmd);
                da.Fill(ds);
                da.Dispose();
                cmd.Dispose();
                cn.Close();
                return ds;
            }
            /// <summary>
            /// Executes the dataset from a populated Command object.
            /// </summary>
            /// <param name="cmd">Fully populated SQLiteCommand</param>
            /// <returns>DataSet</returns>
            public static DataSet ExecuteDataset(SQLiteCommand cmd)
            {
                if (cmd.Connection.State == ConnectionState.Closed)
                    cmd.Connection.Open();
                DataSet ds = new DataSet();
                SQLiteDataAdapter da = new SQLiteDataAdapter(cmd);
                da.Fill(ds);
                da.Dispose();
                cmd.Connection.Close();
                cmd.Dispose();
                return ds;
            }
    
            /// <summary>
            /// Executes the dataset in a SQLite Transaction
            /// </summary>
            /// <param name="transaction">SQLiteTransaction. Transaction consists of Connection, Transaction,  /// and Command, all of which must be created prior to making this method call. </param>
            /// <param name="commandText">Command text.</param>
            /// <param name="commandParameters">Sqlite Command parameters.</param>
            /// <returns>DataSet</returns>
            /// <remarks>user must examine Transaction Object and handle transaction.connection .Close, etc.</remarks>
            public static DataSet ExecuteDataset(SQLiteTransaction transaction, string commandText, params SQLiteParameter[] commandParameters)
            {
    
                if (transaction == null) throw new ArgumentNullException("transaction");
                if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rolled back or committed, please provide an open transaction.", "transaction");
                IDbCommand cmd = transaction.Connection.CreateCommand();
                cmd.CommandText = commandText;
                foreach (SQLiteParameter parm in commandParameters)
                {
                    cmd.Parameters.Add(parm);
                }
                if (transaction.Connection.State == ConnectionState.Closed)
                    transaction.Connection.Open();
                DataSet ds = ExecuteDataset((SQLiteCommand)cmd);
                return ds;
            }
    
            /// <summary>
            /// Executes the dataset with Transaction and object array of parameter values.
            /// </summary>
            /// <param name="transaction">SQLiteTransaction. Transaction consists of Connection, Transaction,    /// and Command, all of which must be created prior to making this method call. </param>
            /// <param name="commandText">Command text.</param>
            /// <param name="commandParameters">object[] array of parameter values.</param>
            /// <returns>DataSet</returns>
            /// <remarks>user must examine Transaction Object and handle transaction.connection .Close, etc.</remarks>
            public static DataSet ExecuteDataset(SQLiteTransaction transaction, string commandText, object[] commandParameters)
            {
    
                if (transaction == null) throw new ArgumentNullException("transaction");
                if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rolled back or committed,                                                          please provide an open transaction.", "transaction");
                IDbCommand cmd = transaction.Connection.CreateCommand();
                cmd.CommandText = commandText;
                AttachParameters((SQLiteCommand)cmd,cmd.CommandText, commandParameters);
                if (transaction.Connection.State == ConnectionState.Closed)
                    transaction.Connection.Open();
    
                DataSet ds = ExecuteDataset((SQLiteCommand)cmd);
                return ds;
            }
    
            #region UpdateDataset
            /// <summary>
            /// Executes the respective command for each inserted, updated, or deleted row in the DataSet.
            /// </summary>
            /// <remarks>
            /// e.g.:  
            ///  UpdateDataset(conn, insertCommand, deleteCommand, updateCommand, dataSet, "Order");
            /// </remarks>
            /// <param name="insertCommand">A valid SQL statement  to insert new records into the data source</param>
            /// <param name="deleteCommand">A valid SQL statement to delete records from the data source</param>
            /// <param name="updateCommand">A valid SQL statement used to update records in the data source</param>
            /// <param name="dataSet">The DataSet used to update the data source</param>
            /// <param name="tableName">The DataTable used to update the data source.</param>
            public static void UpdateDataset(SQLiteCommand insertCommand, SQLiteCommand deleteCommand, SQLiteCommand updateCommand, DataSet dataSet, string tableName)
            {
                if (insertCommand == null) throw new ArgumentNullException("insertCommand");
                if (deleteCommand == null) throw new ArgumentNullException("deleteCommand");
                if (updateCommand == null) throw new ArgumentNullException("updateCommand");
                if (tableName == null || tableName.Length == 0) throw new ArgumentNullException("tableName");
    
                // Create a SQLiteDataAdapter, and dispose of it after we are done
                using (SQLiteDataAdapter dataAdapter = new SQLiteDataAdapter())
                {
                    // Set the data adapter commands
                    dataAdapter.UpdateCommand = updateCommand;
                    dataAdapter.InsertCommand = insertCommand;
                    dataAdapter.DeleteCommand = deleteCommand;
    
                    // Update the dataset changes in the data source
                    dataAdapter.Update(dataSet, tableName);
    
                    // Commit all the changes made to the DataSet
                    dataSet.AcceptChanges();
                }
            }
            #endregion
    
    
    
    
            /// <summary>
            /// ShortCut method to return IDataReader
            /// NOTE: You should explicitly close the Command.connection you passed in as
            /// well as call Dispose on the Command  after reader is closed.
            /// We do this because IDataReader has no underlying Connection Property.
            /// </summary>
            /// <param name="cmd">SQLiteCommand Object</param>
            /// <param name="commandText">SQL Statement with optional embedded "@param" style parameters</param>
            /// <param name="paramList">object[] array of parameter values</param>
            /// <returns>IDataReader</returns>
            public static IDataReader ExecuteReader(SQLiteCommand cmd, string commandText, object[] paramList)
            {
                if (cmd.Connection == null)
                    throw new ArgumentException("Command must have live connection attached.", "cmd");
                cmd.CommandText = commandText;
                AttachParameters(cmd,commandText, paramList);
                if (cmd.Connection.State == ConnectionState.Closed)
                    cmd.Connection.Open();
                IDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                return rdr;
            }
    
            /// <summary>
            /// Shortcut to ExecuteNonQuery with SqlStatement and object[] param values
            /// </summary>
            /// <param name="connectionString">SQLite Connection String</param>
            /// <param name="commandText">Sql Statement with embedded "@param" style parameters</param>
            /// <param name="paramList">object[] array of parameter values</param>
            /// <returns></returns>
            public static int ExecuteNonQuery(string connectionString, string commandText, params object[] paramList)
            {
                SQLiteConnection cn = new SQLiteConnection(connectionString);
                SQLiteCommand cmd = cn.CreateCommand();
                cmd.CommandText = commandText;
                AttachParameters(cmd,commandText, paramList);
                if (cn.State == ConnectionState.Closed)
                    cn.Open();
                int result = cmd.ExecuteNonQuery();
                cmd.Dispose();
                cn.Close();
    
                return result;
            }
    
    
    
            public static int ExecuteNonQuery(SQLiteConnection cn, string commandText, params  object[] paramList)
            {
    
                SQLiteCommand cmd = cn.CreateCommand();
                cmd.CommandText = commandText;
                AttachParameters(cmd,commandText, paramList);
                if (cn.State == ConnectionState.Closed)
                    cn.Open();
                int result = cmd.ExecuteNonQuery();
                cmd.Dispose();
                cn.Close();
    
                return result;
            }
    
            /// <summary>
            /// Executes  non-query sql Statment with Transaction
            /// </summary>
            /// <param name="transaction">SQLiteTransaction. Transaction consists of Connection, Transaction,   /// and Command, all of which must be created prior to making this method call. </param>
            /// <param name="commandText">Command text.</param>
            /// <param name="paramList">Param list.</param>
            /// <returns>Integer</returns>
            /// <remarks>user must examine Transaction Object and handle transaction.connection .Close, etc.</remarks>
            public static int ExecuteNonQuery(SQLiteTransaction transaction, string commandText, params  object[] paramList)
            {
                if (transaction == null) throw new ArgumentNullException("transaction");
                if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rolled back or committed,                                                        please provide an open transaction.", "transaction");
                IDbCommand cmd = transaction.Connection.CreateCommand();
                cmd.CommandText = commandText;
                AttachParameters((SQLiteCommand)cmd,cmd.CommandText, paramList);
                if (transaction.Connection.State == ConnectionState.Closed)
                    transaction.Connection.Open();
                int result = cmd.ExecuteNonQuery();
                cmd.Dispose();
                return result;
            }
    
    
            /// <summary>
            /// Executes the non query.
            /// </summary>
            /// <param name="cmd">CMD.</param>
            /// <returns></returns>
            public static int ExecuteNonQuery(IDbCommand cmd)
            {
                if (cmd.Connection.State == ConnectionState.Closed)
                    cmd.Connection.Open();
                int result = cmd.ExecuteNonQuery();
                cmd.Connection.Close();
                cmd.Dispose();
                return result;
            }
    
            /// <summary>
            /// Shortcut to ExecuteScalar with Sql Statement embedded params and object[] param values
            /// </summary>
            /// <param name="connectionString">SQLite Connection String</param>
            /// <param name="commandText">SQL statment with embedded "@param" style parameters</param>
            /// <param name="paramList">object[] array of param values</param>
            /// <returns></returns>
            public static object ExecuteScalar(string connectionString, string commandText, params  object[] paramList)
            {
                SQLiteConnection cn = new SQLiteConnection(connectionString);
                SQLiteCommand cmd = cn.CreateCommand();
                cmd.CommandText = commandText;
                AttachParameters(cmd,commandText, paramList);
                if (cn.State == ConnectionState.Closed)
                    cn.Open();
                object result = cmd.ExecuteScalar();
                cmd.Dispose();
                cn.Close();
    
                return result;
            }
    
            /// <summary>
            /// Execute XmlReader with complete Command
            /// </summary>
            /// <param name="command">SQLite Command</param>
            /// <returns>XmlReader</returns>
            public static XmlReader ExecuteXmlReader(IDbCommand command)
            { // open the connection if necessary, but make sure we 
                // know to close it when we�re done.
                if (command.Connection.State != ConnectionState.Open)
                {
                    command.Connection.Open();
                }
    
                // get a data adapter  
                SQLiteDataAdapter da = new SQLiteDataAdapter((SQLiteCommand)command);
                DataSet ds = new DataSet();
                // fill the data set, and return the schema information
                da.MissingSchemaAction = MissingSchemaAction.AddWithKey;
                da.Fill(ds);
                // convert our dataset to XML
                StringReader stream = new StringReader(ds.GetXml());
                command.Connection.Close();
                // convert our stream of text to an XmlReader
                return new XmlTextReader(stream);
            }
    
    
    
            /// <summary>
            /// Parses parameter names from SQL Statement, assigns values from object array ,   /// and returns fully populated ParameterCollection.
            /// </summary>
            /// <param name="commandText">Sql Statement with "@param" style embedded parameters</param>
            /// <param name="paramList">object[] array of parameter values</param>
            /// <returns>SQLiteParameterCollection</returns>
            /// <remarks>Status experimental. Regex appears to be handling most issues. Note that parameter object array must be in same ///order as parameter names appear in SQL statement.</remarks>
            private static SQLiteParameterCollection AttachParameters(SQLiteCommand cmd, string commandText, params  object[] paramList)
            {
                if (paramList == null || paramList.Length == 0) return null;
    
                SQLiteParameterCollection coll = cmd.Parameters;
                string parmString = commandText.Substring(commandText.IndexOf("@"));
                // pre-process the string so always at least 1 space after a comma.
                parmString = parmString.Replace(",", " ,");
                // get the named parameters into a match collection
                string pattern = @"(@)S*(.*?)";
                Regex ex = new Regex(pattern, RegexOptions.IgnoreCase);
                MatchCollection mc = ex.Matches(parmString);
                string[] paramNames = new string[mc.Count];
                int i = 0;
                foreach (Match m in mc)
                {
                    paramNames[i] = m.Value;
                    i++;
                }
    
                // now let's type the parameters
                int j = 0;
                Type t = null;
                foreach (object o in paramList)
                {
                    t = o.GetType();
    
                    SQLiteParameter parm = new SQLiteParameter();
                    switch (t.ToString())
                    {
    
                        case ("DBNull"):
                        case ("Char"):
                        case ("SByte"):
                        case ("UInt16"):
                        case ("UInt32"):
                        case ("UInt64"):
                            throw new SystemException("Invalid data type");
    
    
                        case ("System.String"):
                            parm.DbType = DbType.String;
                            parm.ParameterName = paramNames[j];
                            parm.Value = (string)paramList[j];
                            coll.Add(parm);
                            break;
    
                        case ("System.Byte[]"):
                            parm.DbType = DbType.Binary;
                            parm.ParameterName = paramNames[j];
                            parm.Value = (byte[])paramList[j];
                            coll.Add(parm);
                            break;
    
                        case ("System.Int32"):
                            parm.DbType = DbType.Int32;
                            parm.ParameterName = paramNames[j];
                            parm.Value = (int)paramList[j];
                            coll.Add(parm);
                            break;
    
                        case ("System.Boolean"):
                            parm.DbType = DbType.Boolean;
                            parm.ParameterName = paramNames[j];
                            parm.Value = (bool)paramList[j];
                            coll.Add(parm);
                            break;
    
                        case ("System.DateTime"):
                            parm.DbType = DbType.DateTime;
                            parm.ParameterName = paramNames[j];
                            parm.Value = Convert.ToDateTime(paramList[j]);
                            coll.Add(parm);
                            break;
    
                        case ("System.Double"):
                            parm.DbType = DbType.Double;
                            parm.ParameterName = paramNames[j];
                            parm.Value = Convert.ToDouble(paramList[j]);
                            coll.Add(parm);
                            break;
    
                        case ("System.Decimal"):
                            parm.DbType = DbType.Decimal;
                            parm.ParameterName = paramNames[j];
                            parm.Value = Convert.ToDecimal(paramList[j]);
                            break;
    
                        case ("System.Guid"):
                            parm.DbType = DbType.Guid;
                            parm.ParameterName = paramNames[j];
                            parm.Value = (System.Guid)(paramList[j]);
                            break;
    
                        case ("System.Object"):
    
                            parm.DbType = DbType.Object;
                            parm.ParameterName = paramNames[j];
                            parm.Value = paramList[j];
                            coll.Add(parm);
                            break;
    
                        default:
                            throw new SystemException("Value is of unknown data type");
    
                    } // end switch
    
                    j++;
                }
                return coll;
            }
    
            /// <summary>
            /// Executes non query typed params from a DataRow
            /// </summary>
            /// <param name="command">Command.</param>
            /// <param name="dataRow">Data row.</param>
            /// <returns>Integer result code</returns>
            public static int ExecuteNonQueryTypedParams(IDbCommand command, DataRow dataRow)
            {
                int retVal = 0;
    
                // If the row has values, the store procedure parameters must be initialized
                if (dataRow != null && dataRow.ItemArray.Length > 0)
                {
                    // Set the parameters values
                    AssignParameterValues(command.Parameters, dataRow);
    
                    retVal = ExecuteNonQuery(command);
                }
                else
                {
                    retVal = ExecuteNonQuery(command);
                }
    
                return retVal;
            }
    
            /// <summary>
            /// This method assigns dataRow column values to an IDataParameterCollection
            /// </summary>
            /// <param name="commandParameters">The IDataParameterCollection to be assigned values</param>
            /// <param name="dataRow">The dataRow used to hold the command's parameter values</param>
            /// <exception cref="System.InvalidOperationException">Thrown if any of the parameter names are invalid.</exception>
            protected internal static void AssignParameterValues(IDataParameterCollection commandParameters, DataRow dataRow)
            {
                if (commandParameters == null || dataRow == null)
                {
                    // Do nothing if we get no data
                    return;
                }
    
                DataColumnCollection columns = dataRow.Table.Columns;
    
                int i = 0;
                // Set the parameters values
                foreach (IDataParameter commandParameter in commandParameters)
                {
                    // Check the parameter name
                    if (commandParameter.ParameterName == null ||
                     commandParameter.ParameterName.Length <= 1)
                        throw new InvalidOperationException(string.Format(
                               "Please provide a valid parameter name on the parameter #{0},                            the ParameterName property has the following value: '{1}'.",
                         i, commandParameter.ParameterName));
    
                    if (columns.Contains(commandParameter.ParameterName))
                        commandParameter.Value = dataRow[commandParameter.ParameterName];
                    else if (columns.Contains(commandParameter.ParameterName.Substring(1)))
                        commandParameter.Value = dataRow[commandParameter.ParameterName.Substring(1)];
    
                    i++;
                }
            }
    
            /// <summary>
            /// This method assigns dataRow column values to an array of IDataParameters
            /// </summary>
            /// <param name="commandParameters">Array of IDataParameters to be assigned values</param>
            /// <param name="dataRow">The dataRow used to hold the stored procedure's parameter values</param>
            /// <exception cref="System.InvalidOperationException">Thrown if any of the parameter names are invalid.</exception>
            protected void AssignParameterValues(IDataParameter[] commandParameters, DataRow dataRow)
            {
                if ((commandParameters == null) || (dataRow == null))
                {
                    // Do nothing if we get no data
                    return;
                }
    
                DataColumnCollection columns = dataRow.Table.Columns;
    
                int i = 0;
                // Set the parameters values
                foreach (IDataParameter commandParameter in commandParameters)
                {
                    // Check the parameter name
                    if (commandParameter.ParameterName == null ||
                     commandParameter.ParameterName.Length <= 1)
                        throw new InvalidOperationException(string.Format(
                         "Please provide a valid parameter name on the parameter #{0}, the ParameterName property has the following value: '{1}'.",
                         i, commandParameter.ParameterName));
    
                    if (columns.Contains(commandParameter.ParameterName))
                        commandParameter.Value = dataRow[commandParameter.ParameterName];
                    else if (columns.Contains(commandParameter.ParameterName.Substring(1)))
                        commandParameter.Value = dataRow[commandParameter.ParameterName.Substring(1)];
    
                    i++;
                }
            }
    
            /// <summary>
            /// This method assigns an array of values to an array of IDataParameters
            /// </summary>
            /// <param name="commandParameters">Array of IDataParameters to be assigned values</param>
            /// <param name="parameterValues">Array of objects holding the values to be assigned</param>
            /// <exception cref="System.ArgumentException">Thrown if an incorrect number of parameters are passed.</exception>
            protected void AssignParameterValues(IDataParameter[] commandParameters, params  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("Parameter count does not match Parameter Value count.");
                }
    
                // Iterate through the IDataParameters, assigning the values from the corresponding position in the 
                // value array
                for (int i = 0, j = commandParameters.Length, k = 0; i < j; i++)
                {
                    if (commandParameters[i].Direction != ParameterDirection.ReturnValue)
                    {
                        // If the current array value derives from IDataParameter, then assign its Value property
                        if (parameterValues[k] is IDataParameter)
                        {
                            IDataParameter paramInstance;
                            paramInstance = (IDataParameter)parameterValues[k];
                            if (paramInstance.Direction == ParameterDirection.ReturnValue)
                            {
                                paramInstance = (IDataParameter)parameterValues[++k];
                            }
                            if (paramInstance.Value == null)
                            {
                                commandParameters[i].Value = DBNull.Value;
                            }
                            else
                            {
                                commandParameters[i].Value = paramInstance.Value;
                            }
                        }
                        else if (parameterValues[k] == null)
                        {
                            commandParameters[i].Value = DBNull.Value;
                        }
                        else
                        {
                            commandParameters[i].Value = parameterValues[k];
                        }
                        k++;
                    }
                }
            }
        }
    }

    引自 http://www.cnblogs.com/luxiaoxun/p/3784729.html

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  • 原文地址:https://www.cnblogs.com/xinzheng/p/5305012.html
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