I've written a generic database class which can be called to carry out common database (CRUD) operations to save re-writing the ADO.NET code in multiple solutions. To make this flexible, there are a number of constructor overloads based on the different database authentication types and instance types etc. The class is as follows:
class Database
{ // default instance with Windows authentication // constructor 1 public Database(string server, string database, bool persistSecurityInfo) { _server = server; _database = database; _persistSecurityInfo = persistSecurityInfo; _integratedSecurity = "True"; _connectionString = "Data Source=" + server + ";Initial Catalog=" + database + ";Persist Security Info=" + persistSecurityInfo.ToString() + ";Integrated Security=True"; } // named instance using Windows authentication // constructor 2 public Database(string server, string instance, string database, bool persistSecurityInfo) : this(server, database, persistSecurityInfo) { _instance = instance; _integratedSecurity = "True"; _connectionString = "Data Source=" + server + "\" + instance + ";Initial Catalog=" + database + ";Persist Security Info=" + persistSecurityInfo.ToString() + ";Integrated Security=True"; } // default instance with SQL authentication // constructor 3 public Database(string server, string database, bool persistSecurityInfo, string userName, string password) : this(server, database, persistSecurityInfo) { _userName = userName; _password = password; _integratedSecurity = "False"; _connectionString = "Data Source=" + server + ";Initial Catalog=" + database + ";Persist Security Info=" + persistSecurityInfo.ToString() + ";User ID=" + userName + ";Password=" + password; } // named instance with SQL authentication // constructor 4 public Database(string server, string instance, string database, bool persistSecurityInfo, string userName, string password) : this(server, database, persistSecurityInfo, userName, password) { _instance = instance; _integratedSecurity = "False"; _connectionString = "Data Source=" + server + "\" + instance + ";Initial Catalog=" + database + ";Persist Security Info=" + persistSecurityInfo.ToString() + ";User ID=" + userName + ";Password=" + password; } private string _server; private string _instance; private string _database; private bool _persistSecurityInfo; private string _userName; private string _password; private string _integratedSecurity; private string _connectionString; private string _query; //CRUD Methods here
}I have written a console application which is writing to a database. When the application is executed, the user provides some command line switches.
Some of the switches are as follows (There are others relating to the program's operation which I have not included here):
- /s : database server name
- /i : database instance name
- /d : database name
- /n : integrated security (True or False)
- /u : db Username
- /p : db Password
/i, /u and /p are optional (EG if an instance name isn't supplied, the program assumes it is to connect to a default instance on /s)
Therefore, I need the program to, at run time decide which constructor to call based on which arguments have been provided.
pseudo example here
Class Program
{ static void Main(string[] args) { foreach (string arg in args[]) { //code to work out which parameters have been provided here and adds them to array. Also other code which checks integrity such as ensuring there is no username without a password and vice versa etc. string[] suppliedParameters; //if there is a /i , /u , /p parameters, use constructor 4 //if there is a /u and /p but no /i, use constructor 3 //if there is an /i but no /u or /n use constructor 2 //if there is no /i, /u or /n, use constructor 1 } }
}I know I can use reflection to execute the relevant constructor and that I could achieve selection of the constructor using a switch statement in the Main method which carries out the tests in the logic above but am just wondering if there is a maybe a more elegant way to do this?