Basically, replacing switch with design mode is definitely a bug and over-design. Consider that a few lines of code to modify a file can solve the problem, become modified 3-6 classes to achieve the same functionality. Not stupid, what?

Those superstitious design patterns, let's revise this method. See how your final code expands to several times ...

Public virtual Passwordchangeresult ChangePassword (changepasswordrequest request)
{
if (request = = null)
throw new ArgumentNullException ("request");

var result = new Passwordchangeresult ();
if (String.isnullorwhitespace (request. Email))
{
Result. Adderror (_localizationservice.getresource ("Account.ChangePassword.Errors.EmailIsNotProvided"));
return result;
}
if (String.isnullorwhitespace (request. NewPassword))
{
Result. Adderror (_localizationservice.getresource ("Account.ChangePassword.Errors.PasswordIsNotProvided"));
return result;
}

var customer = _customerservice.getcustomerbyemail (Request. Email);
if (customer = = null)
{
Result. Adderror (_localizationservice.getresource ("Account.ChangePassword.Errors.EmailNotFound"));
return result;
}

var requestisvalid = false;
if (Request. validaterequest)
{
Password
String oldpwd = "";
Switch (customer. Passwordformat)
{
Case passwordformat.encrypted:
Oldpwd = _encryptionservice.encrypttext (Request. OldPassword);
Break
Case passwordformat.hashed:
Oldpwd = _encryptionservice.createpasswordhash (Request. OldPassword, customer. PasswordSalt, _customersettings.hashedpasswordformat);
Break
Default
Oldpwd = Request. OldPassword;
Break
}

BOOL Oldpasswordisvalid = Oldpwd = = Customer. Password;
if (!oldpasswordisvalid)
Result. Adderror (_localizationservice.getresource ("Account.ChangePassword.Errors.OldPasswordDoesntMatch"));

if (oldpasswordisvalid)
Requestisvalid = true;
}
Else
Requestisvalid = true;

At this point request is valid
if (requestisvalid)
{
Switch (Request. Newpasswordformat)
{
Case Passwordformat.clear:
{
Customer. Password = Request. NewPassword;
}
Break
Case passwordformat.encrypted:
{
Customer. Password = _encryptionservice.encrypttext (Request. NewPassword);
}
Break
Case passwordformat.hashed:
{
String saltkey = _encryptionservice.createsaltkey (5);
Customer. PasswordSalt = Saltkey;
Customer. Password = _encryptionservice.createpasswordhash (Request. NewPassword, Saltkey, _customersettings.hashedpasswordformat);
}
Break
Default
Break
}
Customer. Passwordformat = Request. Newpasswordformat;
_customerservice.updatecustomer (customer);
}

return result;
}

Basically, replacing switch with design mode is definitely bug and over-design. Consider that a few lines of code to modify a file can solve the problem, become modified 3-6 classes to achieve the same functionality. Not stupid, what?