Check if record in a table exist in a database through ExecuteNonQuery

Question

in my program i need to check if a record in the database already exists in the table using the if statement. using c# i am trying to do this through an sql con

Answer 1

If someday you want to use EF just do:

private MyDb db = new MyDb();

public bool UserExists(string userName, string password){

   return db.Users.Any(x => x.user_name.Equals(userName, StringComparison.InvariantCultureIgnoreCase)
                         && x.password.Equals(password, StringComparison.InvariantCultureIgnoreCase));
}

Or do a generic method, so you can handle multiple entites:

public bool EntityExists(Expression> predicate) where T : class, new()
{
   return db.Set().Any(predicate);
}

Usage:

EntityExists(x => x.user_name.Equals(userName, StringComparison.InvariantCultureIgnoreCase)
                      && x.password.Equals(password, StringComparison.InvariantCultureIgnoreCase));