C#基类库苏飞版--系列教程导航

来源:互联网 发布:装修效果图 设计软件 编辑:程序博客网 时间:2024/05/18 03:29

1.数据访问基础类(基于SQLite),主要是用来访问SQLite数据库的。
2.得到最大值;是否存在;是否存在(基于SQLiteParameter);
3. 执行SQL语句,返回影响的记录数
4.执行多条SQL语句,实现数据库事务。
5.执行带一个存储过程参数的的SQL语句。
6.向数据库里插入图像格式的字段(和上面情况类似的另一种实例)
7.执行一条计算查询结果语句,返回查询结果(object)。
8.执行查询语句,返回SQLiteDataReader
9.执行查询语句,返回DataSet
10.执行SQL语句,返回影响的记录数
11. 执行多条SQL语句,实现数据库事务。
12. 执行一条计算查询结果语句,返回查询结果(object)。
13.执行查询语句,返回SQLiteDataReader
14.执行查询语句还参数,返回DataSet

/// <summary>/// 编 码 人:苏飞/// 联系方式:361983679  /// 更新网站:<a href=\"http://www.sufeinet.com/thread-655-1-1.html\" target=\"_blank\">http://www.sufeinet.com/thread-655-1-1.html</a>/// </summary>using System;using System.Collections;using System.Collections.Specialized;using System.Data;using System.Configuration;using System.Data.SQLite;namespace Maticsoft.DBUtility{    /// <summary>    /// 数据访问基础类(基于SQLite)    /// 可以用户可以修改满足自己项目的需要。    /// </summary>    public abstract class DbHelperSQLite    {        //数据库连接字符串(web.config来配置),可以动态更改connectionString支持多数据库.            public static string connectionString = "连接字符串";        public DbHelperSQLite()        {        }        #region 公用方法               public static int GetMaxID(string FieldName, string TableName)        {            string strsql = "select max(" + FieldName + ")+1 from " + TableName;            object obj = GetSingle(strsql);            if (obj == null)            {                return 1;            }            else            {                return int.Parse(obj.ToString());            }        }        public static bool Exists(string strSql)        {            object obj = GetSingle(strSql);            int cmdresult;            if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))            {                cmdresult = 0;            }            else            {                cmdresult = int.Parse(obj.ToString());            }            if (cmdresult == 0)            {                return false;            }            else            {                return true;            }        }        public static bool Exists(string strSql, params SQLiteParameter[] cmdParms)        {            object obj = GetSingle(strSql, cmdParms);            int cmdresult;            if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))            {                cmdresult = 0;            }            else            {                cmdresult = int.Parse(obj.ToString());            }            if (cmdresult == 0)            {                return false;            }            else            {                return true;            }        }                #endregion        #region  执行简单SQL语句        /// <summary>        /// 执行SQL语句,返回影响的记录数        /// </summary>        /// <param name="SQLString">SQL语句</param>        /// <returns>影响的记录数</returns>        public static int ExecuteSql(string SQLString)        {            using (SQLiteConnection connection = new SQLiteConnection(connectionString))            {                using (SQLiteCommand cmd = new SQLiteCommand(SQLString, connection))                {                    try                    {                        connection.Open();                        int rows = cmd.ExecuteNonQuery();                        return rows;                    }                    catch (System.Data.SQLite.SQLiteException E)                    {                        connection.Close();                        throw new Exception(E.Message);                    }                }            }        }        /// <summary>        /// 执行多条SQL语句,实现数据库事务。        /// </summary>        /// <param name="SQLStringList">多条SQL语句</param>            public static void ExecuteSqlTran(ArrayList SQLStringList)        {            using (SQLiteConnection conn = new SQLiteConnection(connectionString))            {                conn.Open();                SQLiteCommand cmd = new SQLiteCommand();                cmd.Connection = conn;                SQLiteTransaction tx = conn.BeginTransaction();                cmd.Transaction = tx;                try                {                    for (int n = 0; n < SQLStringList.Count; n++)                    {                        string strsql = SQLStringList[n].ToString();                        if (strsql.Trim().Length > 1)                        {                            cmd.CommandText = strsql;                            cmd.ExecuteNonQuery();                        }                    }                    tx.Commit();                }                catch (System.Data.SQLite.SQLiteException E)                {                    tx.Rollback();                    throw new Exception(E.Message);                }            }        }        /// <summary>        /// 执行带一个存储过程参数的的SQL语句。        /// </summary>        /// <param name="SQLString">SQL语句</param>        /// <param name="content">参数内容,比如一个字段是格式复杂的文章,有特殊符号,可以通过这个方式添加</param>        /// <returns>影响的记录数</returns>        public static int ExecuteSql(string SQLString, string content)        {            using (SQLiteConnection connection = new SQLiteConnection(connectionString))            {                SQLiteCommand cmd = new SQLiteCommand(SQLString, connection);                SQLiteParameter myParameter = new SQLiteParameter("@content", DbType.String);                myParameter.Value = content;                cmd.Parameters.Add(myParameter);                try                {                    connection.Open();                    int rows = cmd.ExecuteNonQuery();                    return rows;                }                catch (System.Data.SQLite.SQLiteException E)                {                    throw new Exception(E.Message);                }                finally                {                    cmd.Dispose();                    connection.Close();                }            }        }        /// <summary>        /// 向数据库里插入图像格式的字段(和上面情况类似的另一种实例)        /// </summary>        /// <param name="strSQL">SQL语句</param>        /// <param name="fs">图像字节,数据库的字段类型为image的情况</param>        /// <returns>影响的记录数</returns>        public static int ExecuteSqlInsertImg(string strSQL, byte[] fs)        {            using (SQLiteConnection connection = new SQLiteConnection(connectionString))            {                SQLiteCommand cmd = new SQLiteCommand(strSQL, connection);                SQLiteParameter myParameter = new SQLiteParameter("@fs", DbType.Binary);                myParameter.Value = fs;                cmd.Parameters.Add(myParameter);                try                {                    connection.Open();                    int rows = cmd.ExecuteNonQuery();                    return rows;                }                catch (System.Data.SQLite.SQLiteException E)                {                    throw new Exception(E.Message);                }                finally                {                    cmd.Dispose();                    connection.Close();                }            }        }        /// <summary>        /// 执行一条计算查询结果语句,返回查询结果(object)。        /// </summary>        /// <param name="SQLString">计算查询结果语句</param>        /// <returns>查询结果(object)</returns>        public static object GetSingle(string SQLString)        {            using (SQLiteConnection connection = new SQLiteConnection(connectionString))            {                using (SQLiteCommand cmd = new SQLiteCommand(SQLString, connection))                {                    try                    {                        connection.Open();                        object obj = cmd.ExecuteScalar();                        if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))                        {                            return null;                        }                        else                        {                            return obj;                        }                    }                    catch (System.Data.SQLite.SQLiteException e)                    {                        connection.Close();                        throw new Exception(e.Message);                    }                }            }        }        /// <summary>        /// 执行查询语句,返回SQLiteDataReader        /// </summary>        /// <param name="strSQL">查询语句</param>        /// <returns>SQLiteDataReader</returns>        public static SQLiteDataReader ExecuteReader(string strSQL)        {            SQLiteConnection connection = new SQLiteConnection(connectionString);            SQLiteCommand cmd = new SQLiteCommand(strSQL, connection);            try            {                connection.Open();                SQLiteDataReader myReader = cmd.ExecuteReader();                return myReader;            }            catch (System.Data.SQLite.SQLiteException e)            {                throw new Exception(e.Message);            }        }        /// <summary>        /// 执行查询语句,返回DataSet        /// </summary>        /// <param name="SQLString">查询语句</param>        /// <returns>DataSet</returns>        public static DataSet Query(string SQLString)        {            using (SQLiteConnection connection = new SQLiteConnection(connectionString))            {                DataSet ds = new DataSet();                try                {                    connection.Open();                    SQLiteDataAdapter command = new SQLiteDataAdapter(SQLString, connection);                    command.Fill(ds, "ds");                }                catch (System.Data.SQLite.SQLiteException ex)                {                    throw new Exception(ex.Message);                }                return ds;            }        }        #endregion        #region 执行带参数的SQL语句        /// <summary>        /// 执行SQL语句,返回影响的记录数        /// </summary>        /// <param name="SQLString">SQL语句</param>        /// <returns>影响的记录数</returns>        public static int ExecuteSql(string SQLString, params SQLiteParameter[] cmdParms)        {            using (SQLiteConnection connection = new SQLiteConnection(connectionString))            {                using (SQLiteCommand cmd = new SQLiteCommand())                {                    try                    {                        PrepareCommand(cmd, connection, null, SQLString, cmdParms);                        int rows = cmd.ExecuteNonQuery();                        cmd.Parameters.Clear();                        return rows;                    }                    catch (System.Data.SQLite.SQLiteException E)                    {                        throw new Exception(E.Message);                    }                }            }        }        /// <summary>        /// 执行多条SQL语句,实现数据库事务。        /// </summary>        /// <param name="SQLStringList">SQL语句的哈希表(key为sql语句,value是该语句的SQLiteParameter[])</param>        public static void ExecuteSqlTran(Hashtable SQLStringList)        {            using (SQLiteConnection conn = new SQLiteConnection(connectionString))            {                conn.Open();                using (SQLiteTransaction trans = conn.BeginTransaction())                {                    SQLiteCommand cmd = new SQLiteCommand();                    try                    {                        //循环                        foreach (DictionaryEntry myDE in SQLStringList)                        {                            string cmdText = myDE.Key.ToString();                            SQLiteParameter[] cmdParms = (SQLiteParameter[])myDE.Value;                            PrepareCommand(cmd, conn, trans, cmdText, cmdParms);                            int val = cmd.ExecuteNonQuery();                            cmd.Parameters.Clear();                            trans.Commit();                        }                    }                    catch                    {                        trans.Rollback();                        throw;                    }                }            }        }        /// <summary>        /// 执行一条计算查询结果语句,返回查询结果(object)。        /// </summary>        /// <param name="SQLString">计算查询结果语句</param>        /// <returns>查询结果(object)</returns>        public static object GetSingle(string SQLString, params SQLiteParameter[] cmdParms)        {            using (SQLiteConnection connection = new SQLiteConnection(connectionString))            {                using (SQLiteCommand cmd = new SQLiteCommand())                {                    try                    {                        PrepareCommand(cmd, connection, null, SQLString, cmdParms);                        object obj = cmd.ExecuteScalar();                        cmd.Parameters.Clear();                        if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))                        {                            return null;                        }                        else                        {                            return obj;                        }                    }                    catch (System.Data.SQLite.SQLiteException e)                    {                        throw new Exception(e.Message);                    }                }            }        }        /// <summary>        /// 执行查询语句,返回SQLiteDataReader        /// </summary>        /// <param name="strSQL">查询语句</param>        /// <returns>SQLiteDataReader</returns>        public static SQLiteDataReader ExecuteReader(string SQLString, params SQLiteParameter[] cmdParms)        {            SQLiteConnection connection = new SQLiteConnection(connectionString);            SQLiteCommand cmd = new SQLiteCommand();            try            {                PrepareCommand(cmd, connection, null, SQLString, cmdParms);                SQLiteDataReader myReader = cmd.ExecuteReader();                cmd.Parameters.Clear();                return myReader;            }            catch (System.Data.SQLite.SQLiteException e)            {                throw new Exception(e.Message);            }        }        /// <summary>        /// 执行查询语句,返回DataSet        /// </summary>        /// <param name="SQLString">查询语句</param>        /// <returns>DataSet</returns>        public static DataSet Query(string SQLString, params SQLiteParameter[] cmdParms)        {            using (SQLiteConnection connection = new SQLiteConnection(connectionString))            {                SQLiteCommand cmd = new SQLiteCommand();                PrepareCommand(cmd, connection, null, SQLString, cmdParms);                using (SQLiteDataAdapter da = new SQLiteDataAdapter(cmd))                {                    DataSet ds = new DataSet();                    try                    {                        da.Fill(ds, "ds");                        cmd.Parameters.Clear();                    }                    catch (System.Data.SQLite.SQLiteException ex)                    {                        throw new Exception(ex.Message);                    }                    return ds;                }            }        }        private static void PrepareCommand(SQLiteCommand cmd, SQLiteConnection conn, SQLiteTransaction trans, string cmdText, SQLiteParameter[] cmdParms)        {            if (conn.State != ConnectionState.Open)                conn.Open();            cmd.Connection = conn;            cmd.CommandText = cmdText;            if (trans != null)                cmd.Transaction = trans;            cmd.CommandType = CommandType.Text;//cmdType;            if (cmdParms != null)            {                foreach (SQLiteParameter parm in cmdParms)                    cmd.Parameters.Add(parm);            }        }        #endregion    }} 


 

原创粉丝点击