Model returning null value - asp.net-mvc

Question

This is my code for my model
public class ManufacturerModel
{
public int ProductTYpeId { get; set; }
public int Id { get; set; }
public string Name { get; set; }
public List<SelectListItem> manf { get; set; }
public Manufacturer manufacturer { get; set; }
}
This is my code in cshtml file
#using (Html.BeginForm("addmanufacturer", "Admin", FormMethod.Post, new { id = "formPageID" }))
{
<div class="row">
<label>Select Existing Manufacturer<span style="color: Red">*</span>:</label>
<div class="formRight">
#Html.DropDownList("Id", Model.manf)
</div>
</div>
<div class="row">
<label>Manufacturer Name<span style="color: Red">*</span>:</label>
<div class="formRight">
#Html.TextBoxFor(m => m.manufacturer.name)
#Html.ValidationMessageFor(m => m.manufacturer.name)
</div>
</div>
}
I am posting this form and when I am trying to fetch the value from the manfacurer ie - ManufacturerModel manufacturer = new ManufacturerModel();
using a model object all the value are coming out null.
in the text box If I replace it with m => m.Name then I am able to get proper value of Name.
can any one suggest what the problem is
I am using the manf to bind a dropdown. If In case I post back the form and the if it is return the value becomes blank, I need to refill the value..
public ActionResult addmanufacturer(string id)
{
if (id == null)
id = "0";
ManufacturerModel manufacturer = new ManufacturerModel();
manufacturer.ProductTYpeId = Convert.ToInt32(id);
manufacturer.manf = GetManf();
manufacturer.Id = -1;
return View(manufacturer);
}

Answer 1

I think problem will be becouse of:
#using (Html.BeginForm("Action", "Controller", FormMethod, HTML ATTRIBUTES )) { }
You probably want this overload:
#using (Html.BeginForm("Action", "Controller", Route Values, FormMethod, html attributes )) { }
Important is say him that you want route values and not a html atrributes, so try this
#using (Html.BeginForm("addmanufacturer", "Admin", new { id = "formPageID" }, FormMethod.Post, null )) { }
Hope, it helps.
M.