基于SQLite 的配置库的实现
vs2010 本身 有appconfig 配置方面的类，闲来无事，正好最近正在看System.Data.SQLite.dll，所以就有了本篇文章。
首先要用到 sqlite3.dll 这个动态库文件可以到网上去下载，百度一搜会有很多所以，这里就不提供现在地址了。
下面就将实现的例程贴出来供大家指正：
1、创建一个新的项目，选择Windows 窗体应用程序，如下图所示：
2、接下来在项目中引用下载的System.Data.SQLite.dll
3、在项目中添加一个类，名称为：SqliteHelper 。本类是在网上搜集到的，忘记了出处，仅在此处贴出源码，如下：
class SqliteHelper
{
private string connStr = "";
public SqliteHelper(string dbName, bool isFullPath)
{
if (isFullPath)
{
connStr = @"Data Source=" + dbName + ";Initial Catalog=sqlite;Integrated Security=True;Max Pool Size=10";
}
else
{
connStr = @"Data Source=" + System.Environment.CurrentDirectory + "\\" + dbName + ";Initial Catalog=sqlite;Integrated Security=True;Max Pool Size=10";
}
}
/// <summary>
/// 功能: 创建数据库，带路径
/// [2011-10-24 14:16 Bee]<para />
/// </summary>
/// <param name="dbName"></param>
public void CreateDB(string dbName, bool isFullPath)
{
if (isFullPath)
{
if (!File.Exists(dbName))
{
SQLiteConnection.CreateFile(dbName);
}
}
else
{
if (!File.Exists(System.Environment.CurrentDirectory + "\\" + dbName))
{
SQLiteConnection.CreateFile(System.Environment.CurrentDirectory + "\\" + dbName);
}
}
}
/// <summary>
/// 功能: 执行sql，不返回
/// [2011-10-24 14:15 Bee]<para />
/// </summary>
/// <param name="sqlStr">要执行的sql</param>
public void ExecuteSql(string sqlStr)
{
using (SQLiteConnection conn = new SQLiteConnection(connStr))
{
conn.Open();
DbCommand comm = conn.CreateCommand();
comm.CommandText = sqlStr;
comm.CommandType = CommandType.Text;
comm.ExecuteNonQuery();
}
}
/// <summary>
/// 功能: 执行sql语句数组
/// [2011-10-24 14:54 Bee]<para />
/// </summary>
/// <param name="sqlStr"></param>
public void ExecuteSqlList(string[] sqlStr)
{
using (SQLiteConnection conn = new SQLiteConnection(connStr))
{
conn.Open();
SQLiteCommand comm = conn.CreateCommand();
foreach (string item in sqlStr)
{
comm.CommandText = item;
comm.CommandType = CommandType.Text;
comm.ExecuteNonQuery();
}
}
}
/// <summary>
/// 功能: 执行sql返回deteset
/// [2011-10-24 14:15 Bee]<para />
/// </summary>
/// <param name="sqlStr"></param>
/// <returns></returns>
public DataSet ExecDataSet(string sqlStr)
{
using (SQLiteConnection conn = new SQLiteConnection(connStr))
{
conn.Open();
SQLiteCommand cmd = conn.CreateCommand();
cmd.CommandText = sqlStr;
cmd.CommandType = CommandType.Text;
DbDataAdapter da = new SQLiteDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
return ds;
}
}
public object ExecDataAdp(string sqlStr)
{
using (SQLiteConnection conn = new SQLiteConnection(connStr))
{
conn.Open();
SQLiteCommand cmd = conn.CreateCommand();
cmd.CommandText = sqlStr;
cmd.CommandType = CommandType.Text;
object var = cmd.ExecuteScalar();
return var;
}
}
/// <summary>
/// 功能：根据提供的表，返回表的所有列的结果集
/// </summary>
/// <param name="tbname"></param>
/// <returns></returns>
public DataSet ExecuteDataSet(string tbname)
{
DataSet ds = new DataSet();
string Strsql = "select * from " + tbname;
ds = ExecDataSet(Strsql);
return ds;
}
/// <summary>
/// 功能: 判断表是否存在
/// [2011-10-24 14:14 Bee]<para />
/// </summary>
/// <param name="tableName"></param>
/// <returns>存在不存在</returns>
public bool IsTableExist(string tableName)
{
using (SQLiteConnection connection = new SQLiteConnection(connStr))
{
connection.Open();
using (SQLiteCommand command = new SQLiteCommand(connection))
{
command.CommandText = "SELECT COUNT(*) FROM sqlite_master where type='table' and name='" + tableName + "'";
int iaaa = Convert.ToInt32(command.ExecuteScalar());
if (Convert.ToInt32(command.ExecuteScalar()) == 0)
{
return false;
}
else
{
return true;
}
}
}
}
}
{
private string dbconfig = string.Empty;
public AppConfig()
{
dbconfig = "AppConfig.db3";
}
/// <summary>
/// 创建配置数据库
/// </summary>
public void createDBAppConfig()
{
SqliteHelper shl = new SqliteHelper(this.dbconfig,false);
shl.CreateDB(this.dbconfig, false);
}
/// <summary>
/// 创建配置表
/// </summary>
public void createTBAppConfig()
{
SqliteHelper shl = new SqliteHelper(this.dbconfig, false);
if (!shl.IsTableExist("AppConfig"))
{
shl.ExecuteSql("create table AppConfig(key varchar(30),value varchar(100),PRIMARY KEY (KEY));");
}
}
/// <summary>
/// 加载配置数据，如果不存在，先添加再加载
/// </summary>
/// <param name="strKey">关键字</param>
/// <returns>返回关键字的键值</returns>
public string LoadKey(string strKey)
{
if (!IsExistsKey(strKey))
{
SaveKey(strKey,"");
}
string strValue="";
SqliteHelper shl = new SqliteHelper(this.dbconfig, false);
strValue = shl.ExecDataAdp("select value from AppConfig where key = '" + strKey + "';").ToString();
return strValue;
}
/// <summary>
/// 判断关键字是否存在
/// </summary>
/// <param name="strKey">关键字</param>
/// <returns>返回一个布尔值</returns>
public bool IsExistsKey(string strKey)
{
bool bReturn = false;
int iRows = 0;
SqliteHelper shl = new SqliteHelper(this.dbconfig, false);
iRows = Convert.ToInt32(shl.ExecDataAdp("select count(1) from AppConfig where key = '" + strKey + "';"));
if (iRows != 0) bReturn = true;
return bReturn;
}
/// <summary>
/// 更新配置数据
/// </summary>
/// <param name="strKey">关键字</param>
/// <param name="strValue">配置值</param>
public void SaveKey(string strKey, string strValue)
{
SqliteHelper shl = new SqliteHelper(this.dbconfig, false);
shl.ExecuteSql("replace into AppConfig values('" + strKey + "','" + strValue + "');");
}
/// <summary>
/// 删除关键字
/// </summary>
/// <param name="strKey"></param>
public void DeleteKey(string strKey)
{
if (IsExistsKey(strKey))
{
SqliteHelper shl = new SqliteHelper(this.dbconfig, false);
shl.ExecuteSql("delete from AppConfig where key = '" + strKey + "';");
}
}
}
public Form1()
{
InitializeComponent();
}
{
//判断是否存在配置库及配置表，只有第一次起作用，若存在 将不执行
app.createDBAppConfig();
app.createTBAppConfig();
tb_port.Text = app.LoadKey("port");
tb_user.Text = app.LoadKey("user");
tb_pwd.Text = app.LoadKey("pwd");
tb_db.Text = app.LoadKey("dbname");
//app.SaveKey("server", "127.0.0.1");
//app.DeleteKey("a1111");
}
{
app.SaveKey("server", tb_server.Text);
app.SaveKey("port", tb_port.Text);
app.SaveKey("user", tb_user.Text);
app.SaveKey("pwd", tb_pwd.Text);
app.SaveKey("dbname", tb_db.Text);
//app.DeleteKey("a1111");
}
{
this.Close();
}