// the interface is applied so as to reduce tight coupling between the method and bankAccounts
// You can change it if you want, it's quite flexible.... i think.
public static Account Login(IBankAccounts bankAccounts, string accountNumber, string password)
{
var checkExistence = bankAccounts.AccountExists(accountNumber);
if (checkExistence)
{
var checkDetails = bankAccounts.AccountLoginMatch(accountNumber, password);
if (checkDetails)
{
var UserAccount = bankAccounts.returnAccount(accountNumber);
return(UserAccount);
}
}
return(null);
}