Can you use nested view models in ASP.net MVC3?

Question

Here is a simplified version of what I am doing.

I have created a view model that contains data for a Company. The company has 3 addresses. So trying to be clever I created an AddressViewModel and an _address partial.

The problem I have is that while I can pass the AddressViewModel to the partial and it renders the address I now have duplicate id's in the HTML... so there are now three "Line1" input fields on the form which of course don't post back properly.

How can I resolve this issue. Is the only way to really flatten the ViewModel and have,

MainAddressLine1 MailAddressLine1 BillAddressLine1

in the company view model? And, if I do this, can I still use the _address partial in some way?

Answer 1

Use an editor template instead of a partial:

@model MainViewModel
@using (Html.BeginForm())
{
    @Html.EditorFor(x => x.MainAddress)
    @Html.EditorFor(x => x.MailAddress)
    @Html.EditorFor(x => x.BillAddress)

    <button type="submit">OK</button>
}

and then inside ~/Views/Shared/EditorTemplates/AddressViewModel.cshtml:

@model AddressViewModel
@Html.EditorFor(x => x.Street)
@Html.EditorFor(x => x.ZipCode)
...

Now you don't have to worry about the names and ids of the input fields. They will be correctly handled.