sqliteprovider.cs

一种.net实现ajax方法的类库

/** Copyright (c) 2006, All-In-One Creations, Ltd.
*  All rights reserved.
* 
* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
* 
*     * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
*     * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
*     * Neither the name of All-In-One Creations, Ltd. nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
* 
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**//*: emergetk: stateful web framework for the masses
 * File name: SQLiteProvider.cs
 * Description: SQLite Data Provider implementation.
 *   
 * Author: Ben Joldersma
 *   
 */

using System;
#if MONO
using Mono.Data.SqliteClient;
#else
using System.Data.SQLite;
#endif
using System.Collections.Generic;
using System.Text;
using System.Data;
using System.Reflection;

namespace EmergeTk.Model
{
    public enum SqlExecutionType
    {
        Scalar,
        NonQuery,
        Reader,
        DataTable
    }
    public sealed class SQLiteProvider : DataProvider
    {
        private static readonly SQLiteProvider provider = new SQLiteProvider();

        private SQLiteProvider() { DataProvider.RegisterProvider(typeof(SQLiteRecord),this); }

        static public SQLiteProvider Provider { get { return provider; } }

        public static T Execute<T>(string sql, SqlExecutionType mode, bool wrapTransaction) where T : class
        {
            string dbPath = Util.RootPath + "data.db";
            System.Console.WriteLine("dbPath:" + dbPath);
#if MONO
            SqliteConnection conn = new SqliteConnection("URI=file:" + dbPath);
#else
            SQLiteConnection conn = new SQLiteConnection("Data Source=" + dbPath);
#endif
            conn.Open();
        	IDbCommand cmd = conn.CreateCommand();
            IDbTransaction trans = null;
            if( wrapTransaction ) trans = conn.BeginTransaction();
            cmd.CommandText = sql;
            T retVal = null;

            switch (mode)
            {
                case SqlExecutionType.Scalar:
                    retVal = (T)cmd.ExecuteScalar();
                    break;
                case SqlExecutionType.NonQuery:
                    cmd.ExecuteNonQuery();
                    break;
                case SqlExecutionType.Reader:
                    retVal = cmd.ExecuteReader() as T;
                    break;
                case SqlExecutionType.DataTable:
#if MONO
                    SqliteDataAdapter da = new SqliteDataAdapter(cmd);
#else
                    SQLiteDataAdapter da = new SQLiteDataAdapter(cmd as SQLiteCommand);
#endif
                    DataTable t= new DataTable();
                    da.Fill(t);
                    retVal = t as T;
                    break;
            }
            
            if( wrapTransaction )trans.Commit();
            if (mode != SqlExecutionType.Reader)
            {
                cmd.Dispose();
                conn.Close();
                conn.Dispose();
            }
            //TODO: need to release resources after reader is complete.
            return retVal;
        }

        public object ExecuteScalar(string sql, bool wrapTransaction)
        {
            return Execute<object>(sql, SqlExecutionType.Scalar, wrapTransaction);
        }

        public void ExecuteNonQuery(string sql, bool wrapTransaction)
        {
            Execute<object>(sql, SqlExecutionType.NonQuery, wrapTransaction);
        }

#if MONO
        public SqliteDataReader ExecuteReader(string sql, bool wrapTransaction)
        {
            return Execute<SqliteDataReader>(sql, SqlExecutionType.Reader, wrapTransaction);
        }
#else
        public SQLiteDataReader ExecuteReader(string sql, bool wrapTransaction)
        {
            return Execute<SQLiteDataReader>(sql, SqlExecutionType.Reader, wrapTransaction);
        }
#endif

        public DataTable ExecuteDataTable(string sql, bool wrapTransaction)
        {
            return Execute<DataTable>(sql, SqlExecutionType.DataTable, wrapTransaction);
        }

        public IRecordList<T> Load<T>() where T : AbstractRecord, new()
        {
            return Load<T>("","ROWID");
        }

        public IRecordList<T> Load<T>(params SortInfo[] sortInfos) where T : AbstractRecord, new()
        {
            return Load<T>(string.Empty, Util.Join(sortInfos));
        }

        public IRecordList<T> Load<T>(string whereClause, string orderByClause) where T : AbstractRecord, new()
        {
            return Load<T>(whereClause, orderByClause, false);
        }

        public IRecordList<T> Load<T>(string whereClause, string orderByClause, bool FastLoad ) where T : AbstractRecord, new()
        {
            if (whereClause != null && whereClause.Length > 0)
            {
                whereClause = " WHERE " + whereClause;
            }
            if (orderByClause != null && orderByClause.Length > 0)
            {
                orderByClause = " ORDER BY " + orderByClause;
            }
            RecordList<T> records = new RecordList<T>();
            Type type = typeof(T);
            string name = type.Name;
            if (!SQLiteRecord.TableExists(name))
                return records;

            string star = FastLoad ? ", *" : "";

            DataTable result = SQLiteProvider.Provider.ExecuteDataTable("SELECT ROWID" + star + " FROM " + name + whereClause + orderByClause, false);

            for (int i = 0; i < result.Rows.Count; i++)
            {
                T r;
                if( FastLoad )
                    r = SQLiteRecord.LoadFromDataRow<T>(result.Rows[i]);
                else
                    r = SQLiteRecord.Load<T>(Convert.ToInt32(result.Rows[i]["ROWID"]));

                records.Add(r);
            }

            return records;
        }

        public IRecordList<T> Load<T>(params FilterInfo[] filterInfos) where T : AbstractRecord, new()
        {
            return Load<T>(Util.Join(filterInfos), string.Empty);
        }

        public IRecordList<T> Load<T>(FilterInfo[] filterInfos, SortInfo[] sortInfos ) where T : AbstractRecord, new()
        {
            return Load<T>(Util.Join(filterInfos), Util.Join(sortInfos));
        }
    }
}