mysqlEasyHelper(待完善)

class mysqlEasyHeper{
    private string _conStr = "server=localhost; user id=root; port=3308; password=root; charset=utf8; pooling=true";
    private MySqlConnection _con;
    public string conState{
        get{
            return _con == null ? "" : _con.State.ToString();
        }
    }
    public MySqlConnection con{
        get{
            if(_con == null){
                getConn();
            }
            return this._con;
        }
    }
    public mysqlEasyHeper(){
        try {
            _con = new MySqlConnection(_conStr);
            _con.Open();
        } catch (Exception e) {
            
            throw e;
        }
    }
    private MySqlConnection getConn(){
        try {
            _con = new MySqlConnection(_conStr);
            _con.Open();
        } catch (Exception) {
            return null;
        }
        return _con;
    }
    private void excuteNoQuery(string queryStr, MySqlConnection connect){
        if(String.IsNullOrEmpty(queryStr)) return;
        MySqlCommand query = new MySqlCommand(queryStr, connect);
        query.ExecuteNonQuery();
    }
    public void createDatabase(string dataName){
        if(string.IsNullOrEmpty(dataName))return;
        string sql = "create database if not exists " + dataName + ";";
        excuteNoQuery(sql, _con);
    }
    public DataTable showDataBases(){
        string sql = "show databases;";
        DataTable dt = null;
        MySqlDataAdapter adapter = null;
        try {
            MySqlCommand query = new MySqlCommand(sql, _con);
            adapter = new MySqlDataAdapter();
            dt = new DataTable();
            adapter.SelectCommand = query;
            adapter.Fill(dt);
            
        } catch (Exception e) {
            return null;
        }finally{
            adapter.Dispose();
        }
        return dt;
    }
    public void dispose(){
        if(_con != null){
            if (_con.State == ConnectionState.Open) {
                _con.Close();
            }
            _con.Dispose();
        }
    }
    public void dbPoolTest(){
        string _conStr = "server=localhost; user id=root; port=3308; password=root; charset=utf8; pooling=false";
        MySqlConnection conn = new MySqlConnection(_conStr);
        conn.Open();
        conn.Close();
    }
    
}