how to add object to a list in a view? - c#-4.0

Question

I have a strongly typed view where I have a form. I display values of a Contact (object) in Textboxes. The contact has a list of functions. I have also a list of all the functions that exist in database. In the view I'm listing all the functions by displaying checkboxes (value : Id of the function, display : name of the function). Before that, I compare the list of the Contact's functions to all to functions and I checked those of the contact. Like that :
#foreach (extranetClient.Models.Classes.FonctionContact fonction in ViewBag.Fonctions)
{
string coche = "";
if ((#Model.ListeFonctions).Where(c => c.IdFonction == fonction.IdFonction).Count() > 0)
{
coche = "checked";
}
<input type="checkbox" #coche id="#fonction.IdFonction" />#fonction.LibelleFonction <br />
}
It looks like that:
But now, if the user checks a checkbox to add a function to the contact, I need to save it in the contact's list. I cannot find how to do that. Somebody has idea ?

Answer 1

First we need to modify your checkboxes so they will post properly. When a checkbox is checked it will be posted like this name=value. But we want all your checkboxes to be posted into a collection, so the name will follow this format function[x] where x is an index of the checkbox. The value then becomes the ID of the function.
#{
var i = 0;
}
#foreach (extranetClient.Models.Classes.FonctionContact fonction in ViewBag.Fonctions)
{
string coche = "";
if ((#Model.ListeFonctions).Any(c => c.IdFonction == fonction.IdFonction))
{
coche = "checked";
}
<input type="checkbox" #coche id="functions[#(i++)]" value="#fonction.IdFonction" />#fonction.LibelleFonction <br />
}
Now create an action method which can receive the checkboxes's data. Simply provide a parameter which can recieve an enumeration of int assuming your function IDs are ints.
public ActionResult UpdateFunctions(IEnumerable<int> functions)
{
// TODO: functions contains IDs of all checked boxes.
}
Hope this helps.