Handling permissions in a MVP application
- by Chathuranga
In a windows forms payroll application employing MVP pattern (for a small scale client) I'm planing user permission handling as follows (permission based) as basically its implementation should be less complicated and straight forward.
NOTE : System could be simultaneously used by few users (maximum 3) and the database is at the server side.
This is my UserModel. Each user has a list of permissions given for them.
class User
{
string UserID { get; set; }
string Name { get; set; }
string NIC {get;set;}
string Designation { get; set; }
string PassWord { get; set; }
List <string> PermissionList = new List<string>();
bool status { get; set; }
DateTime EnteredDate { get; set; }
}
When user login to the system it will keep the current user in memory.
For example in BankAccountDetailEntering view I control the controller permission as follows.
public partial class BankAccountDetailEntering : Form
{
bool AccountEditable {get; set;}
private void BankAccountDetailEntering_Load(object sender, EventArgs e)
{
cmdEditAccount.enabled = false;
OnLoadForm (sender, e); // Event fires...
If (AccountEditable )
{
cmdEditAccount.enabled=true;
}
}
}
In this purpose my all relevant presenters (like BankAccountDetailPresenter) should aware of UserModel as well in addition to the corresponding business Model it is presenting to the View.
class BankAccountDetailPresenter
{
BankAccountDetailEntering _View;
BankAccount _Model;
User _UserModel;
DataService _DataService;
BankAccountDetailPresenter( BankAccountDetailEntering view, BankAccount model, User userModel, DataService dataService )
{
_View=view;
_Model = model;
_UserModel = userModel;
_DataService = dataService;
WireUpEvents();
}
private void WireUpEvents()
{
_View.OnLoadForm += new EventHandler(_View_OnLoadForm);
}
private void _View_OnLoadForm(Object sender, EventArgs e)
{
foreach(string s in _UserModel.PermissionList)
{
If( s =="CanEditAccount")
{
_View.AccountEditable =true;
return;
}
}
}
public Show()
{
_View.ShowDialog();
}
}
So I'm handling the user permissions in the presenter iterating through the list. Should this be performed in the Presenter or View? Any other more promising ways to do this?
Thanks.
