using System;
using System.Collections.Generic;
using System.Text;
using System.Data.SQLite; //引用
using System.Data;
using System.Data.Common;
namespace MSCL
{
/// <summary>
/// 本类为SQLite数据库帮助类
/// 轻量级数据库SQLite的连接字符串写法："Data Source=D:\database\test.s3db"
/// 轻量级数据库SQLite的加密后的连接字符串写法："Data Source=Maximus.db;Version=3;Password=myPassword;"
/*
string connStr = "Data Source=" + Server.MapPath("~/App_Data/test.db") + ";Version=3;Password=smile;";
DataSet ds = new DataSet();
MSCL.SqliteHelper sqlite = new MSCL.SqliteHelper(connStr);
ds = sqlite.ExecuteDataSet("Select * From LoginTable",CommandType.Text);
*/
/// </summary>
public class SqliteHelper
{
//数据库连接字符串
private readonly string _conn = string.Empty;
public SqliteHelper(string connectionString)
{
_conn = connectionString;
}
#region ExecuteNonQuery
/// <summary>
/// 执行数据库操作(新增、更新或删除)
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="cmd">SqlCommand对象</param>
/// <returns>所受影响的行数</returns>
public int ExecuteNonQuery(SQLiteCommand cmd)
{
int result = 0;
if (string.IsNullOrEmpty(_conn))
throw new ArgumentNullException("Connection string is missing.");
using (SQLiteConnection con = new SQLiteConnection(_conn))
{
SQLiteTransaction trans = null;
PrepareCommand(cmd, con, ref trans, true, cmd.CommandType, cmd.CommandText);
try
{
result = cmd.ExecuteNonQuery();
trans.Commit();
}
catch (Exception ex)
{
trans.Rollback();
throw ex;
}
}
return result;
}
/// <summary>
/// 执行数据库操作(新增、更新或删除)
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="commandText">执行语句或存储过程名</param>
/// <param name="commandType">执行类型</param>
/// <returns>所受影响的行数</returns>
public int ExecuteNonQuery(string commandText, CommandType commandType)
{
int result = 0;
if (string.IsNullOrEmpty(_conn))
throw new ArgumentNullException("Connection string is missing.");
if (string.IsNullOrEmpty(commandText))
throw new ArgumentNullException("commandText");
SQLiteCommand cmd = new SQLiteCommand();
using (SQLiteConnection con = new SQLiteConnection(_conn))
{
SQLiteTransaction trans = null;
PrepareCommand(cmd, con, ref trans, true, commandType, commandText);
try
{
result = cmd.ExecuteNonQuery();
trans.Commit();
}
catch (Exception ex)
{
trans.Rollback();
throw ex;
}
}
return result;
}
/// <summary>
/// 执行数据库操作(新增、更新或删除)
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="commandText">执行语句或存储过程名</param>
/// <param name="commandType">执行类型</param>
/// <param name="cmdParms">SQL参数对象</param>
/// <returns>所受影响的行数</returns>
public int ExecuteNonQuery(string commandText, CommandType commandType, params SQLiteParameter[] cmdParms)
{
int result = 0;
if (string.IsNullOrEmpty(_conn))
throw new ArgumentNullException("Connection string is missing.");
if (string.IsNullOrEmpty(commandText))
throw new ArgumentNullException("commandText");
SQLiteCommand cmd = new SQLiteCommand();
using (SQLiteConnection con = new SQLiteConnection(_conn))
{
SQLiteTransaction trans = null;
PrepareCommand(cmd, con, ref trans, true, commandType, commandText, cmdParms);
try
{
result = cmd.ExecuteNonQuery();
trans.Commit();
}
catch (Exception ex)
{
trans.Rollback();
throw ex;
}
}
return result;
}
#endregion
#region ExecuteScalar
/// <summary>
/// 执行数据库操作(新增、更新或删除)同时返回执行后查询所得的第1行第1列数据
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="cmd">SqlCommand对象</param>
/// <returns>查询所得的第1行第1列数据</returns>
public object ExecuteScalar(SQLiteCommand cmd)
{
object result = 0;
if (string.IsNullOrEmpty(_conn))
throw new ArgumentNullException("Connection string is missing.");
using (SQLiteConnection con = new SQLiteConnection(_conn))
{
SQLiteTransaction trans = null;
PrepareCommand(cmd, con, ref trans, true, cmd.CommandType, cmd.CommandText);
try
{
result = cmd.ExecuteScalar();
trans.Commit();
}
catch (Exception ex)
{
trans.Rollback();
throw ex;
}
}
return result;
}
/// <summary>
/// 执行数据库操作(新增、更新或删除)同时返回执行后查询所得的第1行第1列数据
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="commandText">执行语句或存储过程名</param>
/// <param name="commandType">执行类型</param>
/// <returns>查询所得的第1行第1列数据</returns>
public object ExecuteScalar(string commandText, CommandType commandType)
{
object result = 0;
if (string.IsNullOrEmpty(_conn))
throw new ArgumentNullException("Connection string is missing.");
if (string.IsNullOrEmpty(commandText))
throw new ArgumentNullException("commandText");
SQLiteCommand cmd = new SQLiteCommand();
using (SQLiteConnection con = new SQLiteConnection(_conn))
{
SQLiteTransaction trans = null;
PrepareCommand(cmd, con, ref trans, true, commandType, commandText);
try
{
result = cmd.ExecuteScalar();
trans.Commit();
}
catch (Exception ex)
{
trans.Rollback();
throw ex;
}
}
return result;
}
/// <summary>
/// 执行数据库操作(新增、更新或删除)同时返回执行后查询所得的第1行第1列数据
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="commandText">执行语句或存储过程名</param>
/// <param name="commandType">执行类型</param>
/// <param name="cmdParms">SQL参数对象</param>
/// <returns>查询所得的第1行第1列数据</returns>
public object ExecuteScalar(string commandText, CommandType commandType, params SQLiteParameter[] cmdParms)
{
object result = 0;
if (string.IsNullOrEmpty(_conn))
throw new ArgumentNullException("Connection string is missing.");
if (string.IsNullOrEmpty(commandText))
throw new ArgumentNullException("commandText");
SQLiteCommand cmd = new SQLiteCommand();
using (SQLiteConnection con = new SQLiteConnection(_conn))
{
SQLiteTransaction trans = null;
PrepareCommand(cmd, con, ref trans, true, commandType, commandText);
try
{
result = cmd.ExecuteScalar();
trans.Commit();
}
catch (Exception ex)
{
trans.Rollback();
throw ex;
}
}
return result;
}
#endregion
#region ExecuteReader
/// <summary>
/// 执行数据库查询，返回SqlDataReader对象
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="cmd">SqlCommand对象</param>
/// <returns>SqlDataReader对象</returns>
public DbDataReader ExecuteReader(SQLiteCommand cmd)
{
DbDataReader reader = null;
if (string.IsNullOrEmpty(_conn))
throw new ArgumentNullException("Connection string is missing.");
SQLiteConnection con = new SQLiteConnection(_conn);
SQLiteTransaction trans = null;
PrepareCommand(cmd, con, ref trans, false, cmd.CommandType, cmd.CommandText);
try
{
reader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
}
catch (Exception ex)
{
throw ex;
}
return reader;
}
/// <summary>
/// 执行数据库查询，返回SqlDataReader对象
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="commandText">执行语句或存储过程名</param>
/// <param name="commandType">执行类型</param>
/// <returns>SqlDataReader对象</returns>
public DbDataReader ExecuteReader(string commandText, CommandType commandType)
{
DbDataReader reader = null;
if (string.IsNullOrEmpty(_conn))
throw new ArgumentNullException("Connection string is missing.");
if (string.IsNullOrEmpty(commandText))
throw new ArgumentNullException("commandText");
SQLiteConnection con = new SQLiteConnection(_conn);
SQLiteCommand cmd = new SQLiteCommand();
SQLiteTransaction trans = null;
PrepareCommand(cmd, con, ref trans, false, commandType, commandText);
try
{
reader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
}
catch (Exception ex)
{
throw ex;
}
return reader;
}
/// <summary>
/// 执行数据库查询，返回SqlDataReader对象
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="commandText">执行语句或存储过程名</param>
/// <param name="commandType">执行类型</param>
/// <param name="cmdParms">SQL参数对象</param>
/// <returns>SqlDataReader对象</returns>
public DbDataReader ExecuteReader(string commandText, CommandType commandType, params SQLiteParameter[] cmdParms)
{
DbDataReader reader = null;
if (string.IsNullOrEmpty(_conn))
throw new ArgumentNullException("Connection string is missing.");
if (string.IsNullOrEmpty(commandText))
throw new ArgumentNullException("commandText");
SQLiteConnection con = new SQLiteConnection(_conn);
SQLiteCommand cmd = new SQLiteCommand();
SQLiteTransaction trans = null;
PrepareCommand(cmd, con, ref trans, false, commandType, commandText, cmdParms);
try
{
reader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
}
catch (Exception ex)
{
throw ex;
}
return reader;
}
#endregion
#region ExecuteDataSet
/// <summary>
/// 执行数据库查询，返回DataSet对象
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="cmd">SqlCommand对象</param>
/// <returns>DataSet对象</returns>
public DataSet ExecuteDataSet(SQLiteCommand cmd)
{
DataSet ds = new DataSet();
SQLiteConnection con = new SQLiteConnection(_conn);
SQLiteTransaction trans = null;
PrepareCommand(cmd, con, ref trans, false, cmd.CommandType, cmd.CommandText);
try
{
SQLiteDataAdapter sda = new SQLiteDataAdapter(cmd);
sda.Fill(ds);
}
catch (Exception ex)
{
throw ex;
}
finally
{
if (cmd.Connection != null)
{
if (cmd.Connection.State == ConnectionState.Open)
{
cmd.Connection.Close();
}
}
}
return ds;
}
/// <summary>
/// 执行数据库查询，返回DataSet对象
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="commandText">执行语句或存储过程名</param>
/// <param name="commandType">执行类型</param>
/// <returns>DataSet对象</returns>
public DataSet ExecuteDataSet(string commandText, CommandType commandType)
{
if (string.IsNullOrEmpty(_conn))
throw new ArgumentNullException("Connection string is missing.");
if (string.IsNullOrEmpty(commandText))
throw new ArgumentNullException("commandText");
DataSet ds = new DataSet();
SQLiteConnection con = new SQLiteConnection(_conn);
SQLiteCommand cmd = new SQLiteCommand();
SQLiteTransaction trans = null;
PrepareCommand(cmd, con, ref trans, false, commandType, commandText);
try
{
SQLiteDataAdapter sda = new SQLiteDataAdapter(cmd);
sda.Fill(ds);
}
catch (Exception ex)
{
throw ex;
}
finally
{
if (con != null)
{
if (con.State == ConnectionState.Open)
{
con.Close();
}
}
}
return ds;
}
/// <summary>
/// 执行数据库查询，返回DataSet对象
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="commandText">执行语句或存储过程名</param>
/// <param name="commandType">执行类型</param>
/// <param name="cmdParms">SQL参数对象</param>
/// <returns>DataSet对象</returns>
public DataSet ExecuteDataSet(string commandText, CommandType commandType, params SQLiteParameter[] cmdParms)
{
if (string.IsNullOrEmpty(_conn))
throw new ArgumentNullException("Connection string is missing.");
if (string.IsNullOrEmpty(commandText))
throw new ArgumentNullException("commandText");
DataSet ds = new DataSet();
SQLiteConnection con = null;
SQLiteCommand cmd = new SQLiteCommand();
SQLiteTransaction trans = null;
try
{
con = new SQLiteConnection(_conn);
PrepareCommand(cmd, con, ref trans, false, commandType, commandText, cmdParms);
SQLiteDataAdapter sda = new SQLiteDataAdapter(cmd);
sda.Fill(ds);
}
catch (Exception ex)
{
throw ex;
}
finally
{
if (con != null)
{
if (con.State == ConnectionState.Open)
{
con.Close();
}
}
}
return ds;
}
#endregion
/// <summary>
/// 通用分页查询方法
/// </summary>
/// <param name="connString">连接字符串</param>
/// <param name="tableName">表名</param>
/// <param name="strColumns">查询字段名</param>
/// <param name="strWhere">where条件</param>
/// <param name="strOrder">排序条件</param>
/// <param name="pageSize">每页数据数量</param>
/// <param name="currentIndex">当前页数</param>
/// <param name="recordOut">数据总量</param>
/// <returns>DataTable数据表</returns>
public DataTable SelectPaging(string tableName, string strColumns, string strWhere, string strOrder, int pageSize, int currentIndex, out int recordOut)
{
DataTable dt = new DataTable();
//查询总数
string countSql = "select count(*) from " + tableName + " where {0}";
countSql = String.Format(countSql, strWhere);
recordOut = Convert.ToInt32(ExecuteScalar(countSql, CommandType.Text));
//分页
string pagingTemplate = "select {0} from {1} where {2} order by {3} limit {4} offset {5} ";
int offsetCount = (currentIndex - 1) * pageSize;
string commandText = String.Format(pagingTemplate, strColumns, tableName, strWhere, strOrder, pageSize.ToString(), offsetCount.ToString());
using (DbDataReader reader = ExecuteReader(commandText, CommandType.Text))
{
if (reader != null)
{
dt.Load(reader);
}
}
return dt;
}
/// <summary>
/// 预处理Command对象,数据库链接,事务,需要执行的对象,参数等的初始化
/// </summary>
/// <param name="cmd">Command对象</param>
/// <param name="conn">Connection对象</param>
/// <param name="trans">Transcation对象</param>
/// <param name="useTrans">是否使用事务</param>
/// <param name="cmdType">SQL字符串执行类型</param>
/// <param name="cmdText">SQL Text</param>
/// <param name="cmdParms">SQLiteParameters to use in the command</param>
private void PrepareCommand(SQLiteCommand cmd, SQLiteConnection conn, ref SQLiteTransaction trans, bool useTrans, CommandType cmdType, string cmdText, params SQLiteParameter[] cmdParms)
{
if (conn.State != ConnectionState.Open)
conn.Open();
cmd.Connection = conn;
cmd.CommandText = cmdText;
if (useTrans)
{
trans = conn.BeginTransaction(IsolationLevel.ReadCommitted);
cmd.Transaction = trans;
}
cmd.CommandType = cmdType;
if (cmdParms != null)
{
foreach (SQLiteParameter parm in cmdParms)
cmd.Parameters.Add(parm);
}
}
}
}
轻量级 SQLite数据库帮助类 增删改查 分页
本文转载:CSDN博客