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  • C# SQLite 创建数据库的方法增删查改语法和命令

     

    SQLite介绍

     

    SQLite是一个开源、免费的小型RDBMS(关系型数据库),能独立运行、无服务器、零配置、支持事物,用C实现,内存占用较小,支持绝大数的SQL92标准。

    SQLite数据库官方主页:http://www.sqlite.org/index.html

     

    cmd下sqlite的使用网

     

    1:选择下载对应自己系统的sqlite.3exe文件

     

    2:解压后使用cmd命令进入sqlite3.exe文件所在的路径执行命令就可以操作做相应的操作。

    在进入数据库之后如果需要退出的话windows下摁ctrl+c就能退出

    例如:

    创建数据库命令:sqlite3.exe 【数据库名字.后缀名】

     

      这里比较牛一点的感觉就是创建的数据库后缀名是任意的、不过注意一点就是:在命令框下执行创建数据库的时候。

     

    如果没有为数据库创建表格、则看不见数据库文件,所以必须创建表格。

     

      例如:在CMD命令提示符下输入sqlite3.exe test.db(test.db是数据库名)回车,执行完后,命令提示符自动跳转

     

    到"SQLITE>"状态。这时还是看不到这个数据库!等表格创建或关闭sqlite3

     

    例如:create table user(’用户名‘); 这时可以看到sqlite3.exe所在文件夹下的这个数据库文件了

     

    如果下次还要使用此数据库时仍然使用sqlite3.exe test.db即可进入此数据库 

     

    基础命令(增删改查)

    创建表格命令:create table tablename(字段,字段) 

    这里从命令上可以清楚的看到、在sqlite数据库中创建表格字段的时候、允许不为字段申明数据类型。 

    这是区别于其它关系型数据库的。 

    执行插入命令:insert into tablename values(value,values)

    在、前面我们可以看出、sqlite的操作上和sqlserver没什么太大区别、值得注意的是、insert时区别于sqlserver中、因为sqlserver中允许使用 "insert table  name values(value,value)"这样的省略式擦入。但是sqlite中是不允许使用省略式插入语句的。 

    执行删除语句:delete  from tablename where <条件> 

    删除数据语法和sqlserver相同、 

    删除表则命令为:drop table tablename 

    数据更新命令:update tablename set 字段=值 如果需要条件的话、添加上where语句。 

    执行查询语句:select *from tablename 可跟随where语句

     

    以上就是基础的sqlite的增删查改语法和命令。 

     

    C#操作SQLite Database

    C#下SQLite操作驱动dll下载:System.Data.SQLite

    C#使用SQLite步骤:

    (1)新建一个project

    (2)添加SQLite dll引用(操作驱动)

    (3)使用API操作SQLite DataBase

    操作SQLite Database的C#帮助类SQLite Helper

     1 using System;
     2 using System.Data.SQLite;
     3  
     4 namespace SQLiteSamples
     5 {
     6     class Program
     7     {
     8         //数据库连接
     9         SQLiteConnection m_dbConnection;
    10  
    11         static void Main(string[] args)
    12         {
    13             Program p = new Program();
    14         }
    15  
    16         public Program()
    17         {
    18             createNewDatabase();
    19             connectToDatabase();
    20             createTable();
    21             fillTable();
    22             printHighscores();
    23         }
    24  
    25         //创建一个空的数据库
    26         void createNewDatabase()
    27         {
    28             SQLiteConnection.CreateFile("MyDatabase.sqlite");
    29         }
    30  
    31         //创建一个连接到指定数据库
    32         void connectToDatabase()
    33         {
    34             m_dbConnection = new SQLiteConnection("Data Source=MyDatabase.sqlite;Version=3;");
    35             m_dbConnection.Open();
    36         }
    37  
    38         //在指定数据库中创建一个table
    39         void createTable()
    40         {
    41             string sql = "create table highscores (name varchar(20), score int)";
    42             SQLiteCommand command = new SQLiteCommand(sql, m_dbConnection);
    43             command.ExecuteNonQuery();
    44         }
    45  
    46         //插入一些数据
    47         void fillTable()
    48         {
    49             string sql = "insert into highscores (name, score) values ('Me', 3000)";
    50             SQLiteCommand command = new SQLiteCommand(sql, m_dbConnection);
    51             command.ExecuteNonQuery();
    52  
    53             sql = "insert into highscores (name, score) values ('Myself', 6000)";
    54             command = new SQLiteCommand(sql, m_dbConnection);
    55             command.ExecuteNonQuery();
    56  
    57             sql = "insert into highscores (name, score) values ('And I', 9001)";
    58             command = new SQLiteCommand(sql, m_dbConnection);
    59             command.ExecuteNonQuery();
    60         }
    61  
    62         //使用sql查询语句,并显示结果
    63         void printHighscores()
    64         {
    65             string sql = "select * from highscores order by score desc";
    66             SQLiteCommand command = new SQLiteCommand(sql, m_dbConnection);
    67             SQLiteDataReader reader = command.ExecuteReader();
    68             while (reader.Read())
    69                 Console.WriteLine("Name: " + reader["name"] + "	Score: " + reader["score"]);
    70             Console.ReadLine();
    71         }
    72     }
    73 }
    View Code

    SQLite Helper类

    将一些常用的功能封装一下,封装成SQLite Helper类

      1 using System;
      2 using System.Data;
      3 using System.Text.RegularExpressions;
      4 using System.Xml;
      5 using System.IO;
      6 using System.Collections;
      7 using System.Data.SQLite;
      8  
      9 namespace DBUtility.SQLite
     10 {
     11     /// <summary>
     12     /// SQLiteHelper is a utility class similar to "SQLHelper" in MS
     13     /// Data Access Application Block and follows similar pattern.
     14     /// </summary>
     15     public class SQLiteHelper
     16     {
     17         /// <summary>
     18         /// Creates a new <see cref="SQLiteHelper"/> instance. The ctor is marked private since all members are static.
     19         /// </summary>
     20         private SQLiteHelper()
     21         {
     22         }
     23         /// <summary>
     24         /// Creates the command.
     25         /// </summary>
     26         /// <param name="connection">Connection.</param>
     27         /// <param name="commandText">Command text.</param>
     28         /// <param name="commandParameters">Command parameters.</param>
     29         /// <returns>SQLite Command</returns>
     30         public static SQLiteCommand CreateCommand(SQLiteConnection connection, string commandText, params SQLiteParameter[] commandParameters)
     31         {
     32             SQLiteCommand cmd = new SQLiteCommand(commandText, connection);
     33             if (commandParameters.Length > 0)
     34             {
     35                 foreach (SQLiteParameter parm in commandParameters)
     36                     cmd.Parameters.Add(parm);
     37             }
     38             return cmd;
     39         }
     40  
     41         /// <summary>
     42         /// Creates the command.
     43         /// </summary>
     44         /// <param name="connectionString">Connection string.</param>
     45         /// <param name="commandText">Command text.</param>
     46         /// <param name="commandParameters">Command parameters.</param>
     47         /// <returns>SQLite Command</returns>
     48         public static SQLiteCommand CreateCommand(string connectionString, string commandText, params SQLiteParameter[] commandParameters)
     49         {
     50             SQLiteConnection cn = new SQLiteConnection(connectionString);
     51  
     52             SQLiteCommand cmd = new SQLiteCommand(commandText, cn);
     53  
     54             if (commandParameters.Length > 0)
     55             {
     56                 foreach (SQLiteParameter parm in commandParameters)
     57                     cmd.Parameters.Add(parm);
     58             }
     59             return cmd;
     60         }
     61         /// <summary>
     62         /// Creates the parameter.
     63         /// </summary>
     64         /// <param name="parameterName">Name of the parameter.</param>
     65         /// <param name="parameterType">Parameter type.</param>
     66         /// <param name="parameterValue">Parameter value.</param>
     67         /// <returns>SQLiteParameter</returns>
     68         public static SQLiteParameter CreateParameter(string parameterName, System.Data.DbType parameterType, object parameterValue)
     69         {
     70             SQLiteParameter parameter = new SQLiteParameter();
     71             parameter.DbType = parameterType;
     72             parameter.ParameterName = parameterName;
     73             parameter.Value = parameterValue;
     74             return parameter;
     75         }
     76  
     77         /// <summary>
     78         /// Shortcut method to execute dataset from SQL Statement and object[] arrray of parameter values
     79         /// </summary>
     80         /// <param name="connectionString">SQLite Connection string</param>
     81         /// <param name="commandText">SQL Statement with embedded "@param" style parameter names</param>
     82         /// <param name="paramList">object[] array of parameter values</param>
     83         /// <returns></returns>
     84         public static DataSet ExecuteDataSet(string connectionString, string commandText, object[] paramList)
     85         {
     86             SQLiteConnection cn = new SQLiteConnection(connectionString);
     87             SQLiteCommand cmd = cn.CreateCommand();
     88  
     89  
     90             cmd.CommandText = commandText;
     91             if (paramList != null)
     92             {
     93                 AttachParameters(cmd,commandText, paramList);
     94             }
     95             DataSet ds = new DataSet();
     96             if (cn.State == ConnectionState.Closed)
     97                 cn.Open();
     98             SQLiteDataAdapter da = new SQLiteDataAdapter(cmd);
     99             da.Fill(ds);
    100             da.Dispose();
    101             cmd.Dispose();
    102             cn.Close();
    103             return ds;
    104         }
    105         /// <summary>
    106         /// Shortcut method to execute dataset from SQL Statement and object[] arrray of  parameter values
    107         /// </summary>
    108         /// <param name="cn">Connection.</param>
    109         /// <param name="commandText">Command text.</param>
    110         /// <param name="paramList">Param list.</param>
    111         /// <returns></returns>
    112         public static DataSet ExecuteDataSet(SQLiteConnection cn, string commandText, object[] paramList)
    113         {
    114  
    115             SQLiteCommand cmd = cn.CreateCommand();
    116  
    117  
    118             cmd.CommandText = commandText;
    119             if (paramList != null)
    120             {
    121                 AttachParameters(cmd,commandText, paramList);
    122             }
    123             DataSet ds = new DataSet();
    124             if (cn.State == ConnectionState.Closed)
    125                 cn.Open();
    126             SQLiteDataAdapter da = new SQLiteDataAdapter(cmd);
    127             da.Fill(ds);
    128             da.Dispose();
    129             cmd.Dispose();
    130             cn.Close();
    131             return ds;
    132         }
    133         /// <summary>
    134         /// Executes the dataset from a populated Command object.
    135         /// </summary>
    136         /// <param name="cmd">Fully populated SQLiteCommand</param>
    137         /// <returns>DataSet</returns>
    138         public static DataSet ExecuteDataset(SQLiteCommand cmd)
    139         {
    140             if (cmd.Connection.State == ConnectionState.Closed)
    141                 cmd.Connection.Open();
    142             DataSet ds = new DataSet();
    143             SQLiteDataAdapter da = new SQLiteDataAdapter(cmd);
    144             da.Fill(ds);
    145             da.Dispose();
    146             cmd.Connection.Close();
    147             cmd.Dispose();
    148             return ds;
    149         }
    150  
    151         /// <summary>
    152         /// Executes the dataset in a SQLite Transaction
    153         /// </summary>
    154         /// <param name="transaction">SQLiteTransaction. Transaction consists of Connection, Transaction,  /// and Command, all of which must be created prior to making this method call. </param>
    155         /// <param name="commandText">Command text.</param>
    156         /// <param name="commandParameters">Sqlite Command parameters.</param>
    157         /// <returns>DataSet</returns>
    158         /// <remarks>user must examine Transaction Object and handle transaction.connection .Close, etc.</remarks>
    159         public static DataSet ExecuteDataset(SQLiteTransaction transaction, string commandText, params SQLiteParameter[] commandParameters)
    160         {
    161  
    162             if (transaction == null) throw new ArgumentNullException("transaction");
    163             if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rolled back or committed, please provide an open transaction.", "transaction");
    164             IDbCommand cmd = transaction.Connection.CreateCommand();
    165             cmd.CommandText = commandText;
    166             foreach (SQLiteParameter parm in commandParameters)
    167             {
    168                 cmd.Parameters.Add(parm);
    169             }
    170             if (transaction.Connection.State == ConnectionState.Closed)
    171                 transaction.Connection.Open();
    172             DataSet ds = ExecuteDataset((SQLiteCommand)cmd);
    173             return ds;
    174         }
    175  
    176         /// <summary>
    177         /// Executes the dataset with Transaction and object array of parameter values.
    178         /// </summary>
    179         /// <param name="transaction">SQLiteTransaction. Transaction consists of Connection, Transaction,    /// and Command, all of which must be created prior to making this method call. </param>
    180         /// <param name="commandText">Command text.</param>
    181         /// <param name="commandParameters">object[] array of parameter values.</param>
    182         /// <returns>DataSet</returns>
    183         /// <remarks>user must examine Transaction Object and handle transaction.connection .Close, etc.</remarks>
    184         public static DataSet ExecuteDataset(SQLiteTransaction transaction, string commandText, object[] commandParameters)
    185         {
    186  
    187             if (transaction == null) throw new ArgumentNullException("transaction");
    188             if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rolled back or committed,                                                          please provide an open transaction.", "transaction");
    189             IDbCommand cmd = transaction.Connection.CreateCommand();
    190             cmd.CommandText = commandText;
    191             AttachParameters((SQLiteCommand)cmd,cmd.CommandText, commandParameters);
    192             if (transaction.Connection.State == ConnectionState.Closed)
    193                 transaction.Connection.Open();
    194  
    195             DataSet ds = ExecuteDataset((SQLiteCommand)cmd);
    196             return ds;
    197         }
    198  
    199         #region UpdateDataset
    200         /// <summary>
    201         /// Executes the respective command for each inserted, updated, or deleted row in the DataSet.
    202         /// </summary>
    203         /// <remarks>
    204         /// e.g.: 
    205         ///  UpdateDataset(conn, insertCommand, deleteCommand, updateCommand, dataSet, "Order");
    206         /// </remarks>
    207         /// <param name="insertCommand">A valid SQL statement  to insert new records into the data source</param>
    208         /// <param name="deleteCommand">A valid SQL statement to delete records from the data source</param>
    209         /// <param name="updateCommand">A valid SQL statement used to update records in the data source</param>
    210         /// <param name="dataSet">The DataSet used to update the data source</param>
    211         /// <param name="tableName">The DataTable used to update the data source.</param>
    212         public static void UpdateDataset(SQLiteCommand insertCommand, SQLiteCommand deleteCommand, SQLiteCommand updateCommand, DataSet dataSet, string tableName)
    213         {
    214             if (insertCommand == null) throw new ArgumentNullException("insertCommand");
    215             if (deleteCommand == null) throw new ArgumentNullException("deleteCommand");
    216             if (updateCommand == null) throw new ArgumentNullException("updateCommand");
    217             if (tableName == null || tableName.Length == 0) throw new ArgumentNullException("tableName");
    218  
    219             // Create a SQLiteDataAdapter, and dispose of it after we are done
    220             using (SQLiteDataAdapter dataAdapter = new SQLiteDataAdapter())
    221             {
    222                 // Set the data adapter commands
    223                 dataAdapter.UpdateCommand = updateCommand;
    224                 dataAdapter.InsertCommand = insertCommand;
    225                 dataAdapter.DeleteCommand = deleteCommand;
    226  
    227                 // Update the dataset changes in the data source
    228                 dataAdapter.Update(dataSet, tableName);
    229  
    230                 // Commit all the changes made to the DataSet
    231                 dataSet.AcceptChanges();
    232             }
    233         }
    234         #endregion
    235  
    236  
    237  
    238  
    239         /// <summary>
    240         /// ShortCut method to return IDataReader
    241         /// NOTE: You should explicitly close the Command.connection you passed in as
    242         /// well as call Dispose on the Command  after reader is closed.
    243         /// We do this because IDataReader has no underlying Connection Property.
    244         /// </summary>
    245         /// <param name="cmd">SQLiteCommand Object</param>
    246         /// <param name="commandText">SQL Statement with optional embedded "@param" style parameters</param>
    247         /// <param name="paramList">object[] array of parameter values</param>
    248         /// <returns>IDataReader</returns>
    249         public static IDataReader ExecuteReader(SQLiteCommand cmd, string commandText, object[] paramList)
    250         {
    251             if (cmd.Connection == null)
    252                 throw new ArgumentException("Command must have live connection attached.", "cmd");
    253             cmd.CommandText = commandText;
    254             AttachParameters(cmd,commandText, paramList);
    255             if (cmd.Connection.State == ConnectionState.Closed)
    256                 cmd.Connection.Open();
    257             IDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
    258             return rdr;
    259         }
    260  
    261         /// <summary>
    262         /// Shortcut to ExecuteNonQuery with SqlStatement and object[] param values
    263         /// </summary>
    264         /// <param name="connectionString">SQLite Connection String</param>
    265         /// <param name="commandText">Sql Statement with embedded "@param" style parameters</param>
    266         /// <param name="paramList">object[] array of parameter values</param>
    267         /// <returns></returns>
    268         public static int ExecuteNonQuery(string connectionString, string commandText, params object[] paramList)
    269         {
    270             SQLiteConnection cn = new SQLiteConnection(connectionString);
    271             SQLiteCommand cmd = cn.CreateCommand();
    272             cmd.CommandText = commandText;
    273             AttachParameters(cmd,commandText, paramList);
    274             if (cn.State == ConnectionState.Closed)
    275                 cn.Open();
    276             int result = cmd.ExecuteNonQuery();
    277             cmd.Dispose();
    278             cn.Close();
    279  
    280             return result;
    281         }
    282  
    283  
    284  
    285         public static int ExecuteNonQuery(SQLiteConnection cn, string commandText, params  object[] paramList)
    286         {
    287  
    288             SQLiteCommand cmd = cn.CreateCommand();
    289             cmd.CommandText = commandText;
    290             AttachParameters(cmd,commandText, paramList);
    291             if (cn.State == ConnectionState.Closed)
    292                 cn.Open();
    293             int result = cmd.ExecuteNonQuery();
    294             cmd.Dispose();
    295             cn.Close();
    296  
    297             return result;
    298         }
    299  
    300         /// <summary>
    301         /// Executes  non-query sql Statment with Transaction
    302         /// </summary>
    303         /// <param name="transaction">SQLiteTransaction. Transaction consists of Connection, Transaction,   /// and Command, all of which must be created prior to making this method call. </param>
    304         /// <param name="commandText">Command text.</param>
    305         /// <param name="paramList">Param list.</param>
    306         /// <returns>Integer</returns>
    307         /// <remarks>user must examine Transaction Object and handle transaction.connection .Close, etc.</remarks>
    308         public static int ExecuteNonQuery(SQLiteTransaction transaction, string commandText, params  object[] paramList)
    309         {
    310             if (transaction == null) throw new ArgumentNullException("transaction");
    311             if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rolled back or committed,                                                        please provide an open transaction.", "transaction");
    312             IDbCommand cmd = transaction.Connection.CreateCommand();
    313             cmd.CommandText = commandText;
    314             AttachParameters((SQLiteCommand)cmd,cmd.CommandText, paramList);
    315             if (transaction.Connection.State == ConnectionState.Closed)
    316                 transaction.Connection.Open();
    317             int result = cmd.ExecuteNonQuery();
    318             cmd.Dispose();
    319             return result;
    320         }
    321  
    322  
    323         /// <summary>
    324         /// Executes the non query.
    325         /// </summary>
    326         /// <param name="cmd">CMD.</param>
    327         /// <returns></returns>
    328         public static int ExecuteNonQuery(IDbCommand cmd)
    329         {
    330             if (cmd.Connection.State == ConnectionState.Closed)
    331                 cmd.Connection.Open();
    332             int result = cmd.ExecuteNonQuery();
    333             cmd.Connection.Close();
    334             cmd.Dispose();
    335             return result;
    336         }
    337  
    338         /// <summary>
    339         /// Shortcut to ExecuteScalar with Sql Statement embedded params and object[] param values
    340         /// </summary>
    341         /// <param name="connectionString">SQLite Connection String</param>
    342         /// <param name="commandText">SQL statment with embedded "@param" style parameters</param>
    343         /// <param name="paramList">object[] array of param values</param>
    344         /// <returns></returns>
    345         public static object ExecuteScalar(string connectionString, string commandText, params  object[] paramList)
    346         {
    347             SQLiteConnection cn = new SQLiteConnection(connectionString);
    348             SQLiteCommand cmd = cn.CreateCommand();
    349             cmd.CommandText = commandText;
    350             AttachParameters(cmd,commandText, paramList);
    351             if (cn.State == ConnectionState.Closed)
    352                 cn.Open();
    353             object result = cmd.ExecuteScalar();
    354             cmd.Dispose();
    355             cn.Close();
    356  
    357             return result;
    358         }
    359  
    360         /// <summary>
    361         /// Execute XmlReader with complete Command
    362         /// </summary>
    363         /// <param name="command">SQLite Command</param>
    364         /// <returns>XmlReader</returns>
    365         public static XmlReader ExecuteXmlReader(IDbCommand command)
    366         { // open the connection if necessary, but make sure we
    367             // know to close it when we�re done.
    368             if (command.Connection.State != ConnectionState.Open)
    369             {
    370                 command.Connection.Open();
    371             }
    372  
    373             // get a data adapter 
    374             SQLiteDataAdapter da = new SQLiteDataAdapter((SQLiteCommand)command);
    375             DataSet ds = new DataSet();
    376             // fill the data set, and return the schema information
    377             da.MissingSchemaAction = MissingSchemaAction.AddWithKey;
    378             da.Fill(ds);
    379             // convert our dataset to XML
    380             StringReader stream = new StringReader(ds.GetXml());
    381             command.Connection.Close();
    382             // convert our stream of text to an XmlReader
    383             return new XmlTextReader(stream);
    384         }
    385  
    386  
    387  
    388         /// <summary>
    389         /// Parses parameter names from SQL Statement, assigns values from object array ,   /// and returns fully populated ParameterCollection.
    390         /// </summary>
    391         /// <param name="commandText">Sql Statement with "@param" style embedded parameters</param>
    392         /// <param name="paramList">object[] array of parameter values</param>
    393         /// <returns>SQLiteParameterCollection</returns>
    394         /// <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>
    395         private static SQLiteParameterCollection AttachParameters(SQLiteCommand cmd, string commandText, params  object[] paramList)
    396         {
    397             if (paramList == null || paramList.Length == 0) return null;
    398  
    399             SQLiteParameterCollection coll = cmd.Parameters;
    400             string parmString = commandText.Substring(commandText.IndexOf("@"));
    401             // pre-process the string so always at least 1 space after a comma.
    402             parmString = parmString.Replace(",", " ,");
    403             // get the named parameters into a match collection
    404             string pattern = @"(@)S*(.*?)";
    405             Regex ex = new Regex(pattern, RegexOptions.IgnoreCase);
    406             MatchCollection mc = ex.Matches(parmString);
    407             string[] paramNames = new string[mc.Count];
    408             int i = 0;
    409             foreach (Match m in mc)
    410             {
    411                 paramNames[i] = m.Value;
    412                 i++;
    413             }
    414  
    415             // now let's type the parameters
    416             int j = 0;
    417             Type t = null;
    418             foreach (object o in paramList)
    419             {
    420                 t = o.GetType();
    421  
    422                 SQLiteParameter parm = new SQLiteParameter();
    423                 switch (t.ToString())
    424                 {
    425  
    426                     case ("DBNull"):
    427                     case ("Char"):
    428                     case ("SByte"):
    429                     case ("UInt16"):
    430                     case ("UInt32"):
    431                     case ("UInt64"):
    432                         throw new SystemException("Invalid data type");
    433  
    434  
    435                     case ("System.String"):
    436                         parm.DbType = DbType.String;
    437                         parm.ParameterName = paramNames[j];
    438                         parm.Value = (string)paramList[j];
    439                         coll.Add(parm);
    440                         break;
    441  
    442                     case ("System.Byte[]"):
    443                         parm.DbType = DbType.Binary;
    444                         parm.ParameterName = paramNames[j];
    445                         parm.Value = (byte[])paramList[j];
    446                         coll.Add(parm);
    447                         break;
    448  
    449                     case ("System.Int32"):
    450                         parm.DbType = DbType.Int32;
    451                         parm.ParameterName = paramNames[j];
    452                         parm.Value = (int)paramList[j];
    453                         coll.Add(parm);
    454                         break;
    455  
    456                     case ("System.Boolean"):
    457                         parm.DbType = DbType.Boolean;
    458                         parm.ParameterName = paramNames[j];
    459                         parm.Value = (bool)paramList[j];
    460                         coll.Add(parm);
    461                         break;
    462  
    463                     case ("System.DateTime"):
    464                         parm.DbType = DbType.DateTime;
    465                         parm.ParameterName = paramNames[j];
    466                         parm.Value = Convert.ToDateTime(paramList[j]);
    467                         coll.Add(parm);
    468                         break;
    469  
    470                     case ("System.Double"):
    471                         parm.DbType = DbType.Double;
    472                         parm.ParameterName = paramNames[j];
    473                         parm.Value = Convert.ToDouble(paramList[j]);
    474                         coll.Add(parm);
    475                         break;
    476  
    477                     case ("System.Decimal"):
    478                         parm.DbType = DbType.Decimal;
    479                         parm.ParameterName = paramNames[j];
    480                         parm.Value = Convert.ToDecimal(paramList[j]);
    481                         break;
    482  
    483                     case ("System.Guid"):
    484                         parm.DbType = DbType.Guid;
    485                         parm.ParameterName = paramNames[j];
    486                         parm.Value = (System.Guid)(paramList[j]);
    487                         break;
    488  
    489                     case ("System.Object"):
    490  
    491                         parm.DbType = DbType.Object;
    492                         parm.ParameterName = paramNames[j];
    493                         parm.Value = paramList[j];
    494                         coll.Add(parm);
    495                         break;
    496  
    497                     default:
    498                         throw new SystemException("Value is of unknown data type");
    499  
    500                 } // end switch
    501  
    502                 j++;
    503             }
    504             return coll;
    505         }
    506  
    507         /// <summary>
    508         /// Executes non query typed params from a DataRow
    509         /// </summary>
    510         /// <param name="command">Command.</param>
    511         /// <param name="dataRow">Data row.</param>
    512         /// <returns>Integer result code</returns>
    513         public static int ExecuteNonQueryTypedParams(IDbCommand command, DataRow dataRow)
    514         {
    515             int retVal = 0;
    516  
    517             // If the row has values, the store procedure parameters must be initialized
    518             if (dataRow != null && dataRow.ItemArray.Length > 0)
    519             {
    520                 // Set the parameters values
    521                 AssignParameterValues(command.Parameters, dataRow);
    522  
    523                 retVal = ExecuteNonQuery(command);
    524             }
    525             else
    526             {
    527                 retVal = ExecuteNonQuery(command);
    528             }
    529  
    530             return retVal;
    531         }
    532  
    533         /// <summary>
    534         /// This method assigns dataRow column values to an IDataParameterCollection
    535         /// </summary>
    536         /// <param name="commandParameters">The IDataParameterCollection to be assigned values</param>
    537         /// <param name="dataRow">The dataRow used to hold the command's parameter values</param>
    538         /// <exception cref="System.InvalidOperationException">Thrown if any of the parameter names are invalid.</exception>
    539         protected internal static void AssignParameterValues(IDataParameterCollection commandParameters, DataRow dataRow)
    540         {
    541             if (commandParameters == null || dataRow == null)
    542             {
    543                 // Do nothing if we get no data
    544                 return;
    545             }
    546  
    547             DataColumnCollection columns = dataRow.Table.Columns;
    548  
    549             int i = 0;
    550             // Set the parameters values
    551             foreach (IDataParameter commandParameter in commandParameters)
    552             {
    553                 // Check the parameter name
    554                 if (commandParameter.ParameterName == null ||
    555                  commandParameter.ParameterName.Length <= 1)
    556                     throw new InvalidOperationException(string.Format(
    557                            "Please provide a valid parameter name on the parameter #{0},                            the ParameterName property has the following value: '{1}'.",
    558                      i, commandParameter.ParameterName));
    559  
    560                 if (columns.Contains(commandParameter.ParameterName))
    561                     commandParameter.Value = dataRow[commandParameter.ParameterName];
    562                 else if (columns.Contains(commandParameter.ParameterName.Substring(1)))
    563                     commandParameter.Value = dataRow[commandParameter.ParameterName.Substring(1)];
    564  
    565                 i++;
    566             }
    567         }
    568  
    569         /// <summary>
    570         /// This method assigns dataRow column values to an array of IDataParameters
    571         /// </summary>
    572         /// <param name="commandParameters">Array of IDataParameters to be assigned values</param>
    573         /// <param name="dataRow">The dataRow used to hold the stored procedure's parameter values</param>
    574         /// <exception cref="System.InvalidOperationException">Thrown if any of the parameter names are invalid.</exception>
    575         protected void AssignParameterValues(IDataParameter[] commandParameters, DataRow dataRow)
    576         {
    577             if ((commandParameters == null) || (dataRow == null))
    578             {
    579                 // Do nothing if we get no data
    580                 return;
    581             }
    582  
    583             DataColumnCollection columns = dataRow.Table.Columns;
    584  
    585             int i = 0;
    586             // Set the parameters values
    587             foreach (IDataParameter commandParameter in commandParameters)
    588             {
    589                 // Check the parameter name
    590                 if (commandParameter.ParameterName == null ||
    591                  commandParameter.ParameterName.Length <= 1)
    592                     throw new InvalidOperationException(string.Format(
    593                      "Please provide a valid parameter name on the parameter #{0}, the ParameterName property has the following value: '{1}'.",
    594                      i, commandParameter.ParameterName));
    595  
    596                 if (columns.Contains(commandParameter.ParameterName))
    597                     commandParameter.Value = dataRow[commandParameter.ParameterName];
    598                 else if (columns.Contains(commandParameter.ParameterName.Substring(1)))
    599                     commandParameter.Value = dataRow[commandParameter.ParameterName.Substring(1)];
    600  
    601                 i++;
    602             }
    603         }
    604  
    605         /// <summary>
    606         /// This method assigns an array of values to an array of IDataParameters
    607         /// </summary>
    608         /// <param name="commandParameters">Array of IDataParameters to be assigned values</param>
    609         /// <param name="parameterValues">Array of objects holding the values to be assigned</param>
    610         /// <exception cref="System.ArgumentException">Thrown if an incorrect number of parameters are passed.</exception>
    611         protected void AssignParameterValues(IDataParameter[] commandParameters, params  object[] parameterValues)
    612         {
    613             if ((commandParameters == null) || (parameterValues == null))
    614             {
    615                 // Do nothing if we get no data
    616                 return;
    617             }
    618  
    619             // We must have the same number of values as we pave parameters to put them in
    620             if (commandParameters.Length != parameterValues.Length)
    621             {
    622                 throw new ArgumentException("Parameter count does not match Parameter Value count.");
    623             }
    624  
    625             // Iterate through the IDataParameters, assigning the values from the corresponding position in the
    626             // value array
    627             for (int i = 0, j = commandParameters.Length, k = 0; i < j; i++)
    628             {
    629                 if (commandParameters[i].Direction != ParameterDirection.ReturnValue)
    630                 {
    631                     // If the current array value derives from IDataParameter, then assign its Value property
    632                     if (parameterValues[k] is IDataParameter)
    633                     {
    634                         IDataParameter paramInstance;
    635                         paramInstance = (IDataParameter)parameterValues[k];
    636                         if (paramInstance.Direction == ParameterDirection.ReturnValue)
    637                         {
    638                             paramInstance = (IDataParameter)parameterValues[++k];
    639                         }
    640                         if (paramInstance.Value == null)
    641                         {
    642                             commandParameters[i].Value = DBNull.Value;
    643                         }
    644                         else
    645                         {
    646                             commandParameters[i].Value = paramInstance.Value;
    647                         }
    648                     }
    649                     else if (parameterValues[k] == null)
    650                     {
    651                         commandParameters[i].Value = DBNull.Value;
    652                     }
    653                     else
    654                     {
    655                         commandParameters[i].Value = parameterValues[k];
    656                     }
    657                     k++;
    658                 }
    659             }
    660         }
    661     }
    662 }
    View Code

    Codeproject上的一个封装:http://www.codeproject.com/Articles/746191/SQLite-Helper-Csharp

    关于SQLite的connection string说明:http://www.connectionstrings.com/sqlite/

    SQLite GUI客户端列表:http://www.sqlite.org/cvstrac/wiki?p=ManagementTools

    SQLite Administrator下载地址:http://download.orbmu2k.de/files/sqliteadmin.zip

     

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  • 原文地址:https://www.cnblogs.com/endv/p/6940440.html
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