Couple of thoughts...

First is probably obvious, but just in case - do you need the Offices list as a partial?  If not you can just place this logic in the _FormAjax view which would mean you have the references you need.

If you are doing this for re-use though, perhaps make a custom view model for your Offices partial - e.g. a simple class with two properties - Id and Name - and then at the top of the Offices.cshtml file put (instead of @inherits):

@model IEnumerable<TranscorAstra.Website.Models.OfficeFormModel>

Your code in the view would then become:

@foreach(var office in Model)
{
    <option value="@office.Id">@office.Name</option>
}

And then in the parent view you would project to this model:

@Html.Partial("Offices",Model.Content.Children.Where(x => x.IsVisible()&& x.DocumentTypeAlias=="Office")
 .ToList()
 .Select(x => new OfficeFormModel { Id = x.Id, Name = x.Name))

I've almost certainly got something wrong in the syntax above as haven't tried it directly, but think should work and explain the idea at least.

Hi Andy,

the problem is that in the parent view (_FormAjax.cshtml), Model.Content doesn't work. Intellisense gives me already an error for that. This is caused because, to generate my form and have all the validation I need to use the

@inherits Umbraco.Web.Mvc.UmbracoViewPage<MySite.Models.FormModel>

The problem is that "Model" is an instance of my "FormModel" and my FormModel has no .Content... thus Model.Content gives an error. How can I get the actual "IPublishedContent" in the partial view?

I see what you mean.  Because you are inheriting from UmbracoViewPage though you should get access to the Umbraco helper using @Umbraco and hence could access @Umbraco.TypedContent(id)?  You need to get the id of the current page, but if you can do that the rest of your statement to get the child offices should work.

Another way - with reference to my suggestion above - might be to add IEnumerable<TranscorAstra.Website.Models.OfficeFormModel> as a property of your top level FormModel.  Then in Forms.cshtml - where you do have reference to the Umbraco RenderModel you could do:

@Html.Partial("_FormAjax",newMySite.Models.FormModel { Offices = Model.Content.Children.Where(x => x.IsVisible()&& x.DocumentTypeAlias=="Office")} )

And then in _FormAjax.cshtml:

@Html.Partial("Offices",Model.Offices)

And then then define the model for Offices.cshtml as I suggested above.

Hope that helps you get on track... as you can probably tell I'm finding my way with all this myself!

Andy, sorry I didn't get the hint to create an OfficeFormModel (OfficeModel).

I tried your initial suggestion and created the OfficeModel. In my FormAjax.cshtml I added the code you suggested me:

@Html.Partial("Offices", Model.Content.Children.Where(x => x.IsVisible() && x.DocumentTypeAlias=="Office")
 .ToList()
 .Select(x => new OfficeModel { Id = x.Id, Name = x.Name))

Here I think there is a LINQ issue, because I get this error pointing to the ".Select" line: Cannot convert lambda expression to type 'string' because it is not a delegate type.

I tried to put ".ToList()" in the end, or so add ".ToString()" after x.Id and x.Name but no way, I always get that error. I'm not super experienced in LINQ and I don't know how to fix this... did you try this code in your environment or you coded the answer before testing it? ;)

No, seriously. I'm close to the solution, I feel it, but this little error is blocking me at the moment... any ideas are appreciated, thx again.

Ok you know what, I found a solution, ok I consider it quite ugly, but since the above is not working, I think it's quite ok.

In my FormModel I added this property:

public RenderModel UmbracoModel { get; set; }

In Forms.cshtml I call the partial _FormAjax like this

@Html.Partial("_FormAjax", new MySite.Models.FormModel { UmbracoModel = Model })

In _FormAjax.cshtml, I insert my dropdown like this:

@Html.Partial("_OfficesDropdown", new global::Umbraco.Web.Models.RenderModel(Model.UmbracoModel.Content, Model.UmbracoModel.CurrentCulture))

_OfficesDropdown.cshtml looks like this:

@inherits Umbraco.Web.Mvc.UmbracoTemplatePage

@using umbraco.presentation.nodeFactory
@using umbraco.cms.businesslogic.media

<select id="ddOffices">
@foreach (var page in Model.Content.Children.Where(x => x.IsVisible() && x.DocumentTypeAlias == "Office"))
{
    <option value="@page.Id">@page.Name</option>
}
</select>

So I have to pass the RenderModel from the beginning, else it seems to me that it gets simply lost, no way to retrieve it in a partial... which is what I consider a bit dirty. As I initially wrote, I was expecting (also by reading the umbraco documentation I initially linked) that by using this line in _FormAjax I could at least save 1 time this process of passing the initial RenderModel down to the partials...

@inherits Umbraco.Web.Mvc.UmbracoViewPage<MySite.Models.FormModel>

Whatever, it works, if it's possible to fix the LINQ query then I'll use that way... thx again.

Apart from a misused bracket - penultimate one should be } not ) - it does work OK for me in what I think is an analgous situation.  I read when Googling that message that you might be missing a using System.Linq - but actually I don't have that.  So not sure I'm afraid.  But glad you got a solution anyway.

Hei Andy, I corrected the braket,the syntax looks good at least for intellisense, really strange because I really wanted to try your solution.

Asap I have some free time I will try to debug it, cheers

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